Exploring the Lunar Environment with the Lunar Atmosphere and Dust Environment Explorer South Bay Amateur Radio Association – February 8, 2013 Brian Day LADEE.
Download ReportTranscript Exploring the Lunar Environment with the Lunar Atmosphere and Dust Environment Explorer South Bay Amateur Radio Association – February 8, 2013 Brian Day LADEE.
Slide 1
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 2
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 3
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 4
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 5
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 6
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 7
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 8
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 9
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 10
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 11
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 12
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 13
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 14
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 15
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 16
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 17
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 18
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 19
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 20
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 21
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 22
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 23
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 24
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 25
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 26
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 27
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 28
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 29
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 30
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 31
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 32
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 33
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 34
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 35
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 36
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 37
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 38
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 39
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 40
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 41
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 42
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 43
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 44
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 45
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 46
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 47
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 48
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 2
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 3
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 4
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 5
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 6
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 7
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 8
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 9
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 10
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 11
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 12
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 13
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 14
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 15
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 16
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 17
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 18
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 19
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 20
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 21
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 22
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 23
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 24
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 25
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 26
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 27
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 28
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 29
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 30
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 31
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 32
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 33
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 34
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 35
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 36
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 37
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 38
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 39
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 40
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 41
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 42
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 43
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 44
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 45
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 46
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 47
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions
Slide 48
Exploring the Lunar Environment
with the Lunar Atmosphere and Dust Environment Explorer
South Bay Amateur Radio Association – February 8, 2013
Brian Day
LADEE Mission E/PO Lead
NASA Lunar Science Institute Director of Communication and Outreach
[email protected]
A new generation of robotic lunar explorers is
revolutionizing our understanding of the Moon.
We now recognize the Moon as a dynamic world with surficial and internal
volatiles, active geology, and complex interactions with space weather. All
of these could contribute to a fascinating lunar atmospheric environment.
LRO and LCROSS
Lunar Reconnaissance Orbiter
LRO
Lunar Crater Observation
and Sensing Satellite
LCROSS
LRO and LCROSS
launched together
on an Atlas V rocket
from Cape
Canaveral on June
18, 2009.
LCROSS Mission Concept
•
•
Impact the Moon at 2.5 km/sec with a Centaur upper stage and create an ejecta cloud that
may reach over 10 km about the surface
Observe the impact and ejecta with instruments that can detect water
What did we see?
What did we see?
Cam1_W0000_T3460421m473
Schultz, et al (2010)
(Observed expanded ejecta cloud 10-12 km in diameter at 20s after impact. Visible camera imaged
curtain at t+8s through t+42s, before cloud dropped below sensitivity range).
What did we see?
Water Signatures Detected!
LCROSS Observations with Model Fit
1.2
Brightness
1.15
1.1
1.05
1
0.95
1.3
1.4
1.5
LCROSS / NASA ARC / A. Colaprete
1.6 1.7 1.8 1.9
Wavelength (microns)
2
2.1
2.2
Lunar Reconnaissance Orbiter (LRO)
• LROC – image and map the lunar
surface in unprecedented detail
• LOLA – provide precise global
lunar topographic data through
laser altimetry
• LAMP – remotely probe the
Moon’s permanently shadowed
regions
• CRaTER - characterize the global
lunar radiation environment
• DIVINER – measure lunar surface
temperatures & map
compositional variations
• LEND – measure neutron flux to
study hydrogen concentrations in
lunar soil
Apollo 14 Landing Site Imaged by LRO
On the right, you can see the
descent stage of the lunar
module which carried the
astronauts down to the surface of
the Moon.
On the left, the arrow points to an
instrument package with
experiments left on the Moon by
the astronauts.
In between you can see some
dark squiggly lines – the
footprints of the astronauts.
You Can Help Explore the Moon!
Visit http://cosmoquest.org/mappers/moon/
and
http://www.moonzoo.org/
to see how you can help explore the images from LRO.
The Moon’s Permanently Shadowed Craters
are the Coldest Places We have Found in the
Solar System
•
•
LRO has measured
temperatures as low
as -248 degrees
Celsius, or -415
degrees Fahrenheit
This is colder than
the daytime surface
of Pluto! (-230
Celsius)
LRO’s DIVINER Indicates Widespread Ice at
Lunar Poles
• In South Pole permanently-shadowed craters,
surface deposits of water ice would almost
certainly be stable.
• These areas are surrounded by much larger
permafrost regions where ice could be stable
just beneath the surface.
Water in the Soil
• Chandrayann-1 and two other robot explorers
found small amounts of water away from the poles.
Chandrayaan-1
Deep Impact
Cassini
Lobate Scarps – The Shrinking Moon
Moonquakes – A Whole Lot of Shaking
Going On
• Deep moonquakes about 700 km below the surface, probably caused by
tides.
• Vibrations from the impact of meteorites.
• Thermal quakes caused by the expansion of the frigid crust when first
illuminated.
• Shallow moonquakes 20 or 30 kilometers below
the surface. Up to magnitude 5.5 and over 10
minutes duration!
Gravity Recovery and Interior Laboratory
GRAIL
• Launched Sept 10, 2011. Mission completed December 17, 2012.
• Microwave ranging system precisely measures the distance between the two
satellites.
• Use high-quality gravity field mapping to determine the Moon's interior structure.
• Determine the structure of the lunar interior, from crust to core and to advance
understanding of the thermal evolution of the Moon.
ARTEMIS
• Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s
Interaction with the Sun
• Consists of two orbiters, ARTEMIS-P1 & ARTEMIS P2, formerly part of the
THEMIS mission.
• Moved to lunar L1 and L2 points in 2010 and lunar orbit in 2011.
• Studying the solar wind and its interaction with the lunar surface, the Moon’s
plasma wake, and the Earth’s magnetotail.
•Mission is studying how
solar wind electrifies, alters
and erodes the Moon's
surface.
•The Moon exhibits a long
comet-like sodium tail.
•The Earth passes through
this tail once a month.
•Similarly, the Earth’s
exospheric tail extends
beyond the Moon’s orbit.
•Could provide valuable
clues to the origin of the
lunar atmosphere.
Lunar Atmosphere?
•Yes, but very thin! A cubic
centimeter of Earth's
atmosphere at sea level
contains about 1019
molecules. That same volume
just above the Moon's surface
contains only about 100,000
to a few million molecules.
•It glows most strongly from
atoms of sodium. However,
that is probably a minor
constituent. We still do not
know its composition.
Lunar Exosphere
•An exosphere’s is a tenuous,
collisionless atmosphere.
•The lunar exosphere is bounded by
the lunar surface – a surface boundary
exosphere.
•Consists of a variety of atomic and
molecular species – indicative of
conditions at the Moon (surface,
subsurface).
•Wide variety of processes contribute
to sources, variability, losses.
A Dusty Lunar Sky?
In 1968, NASA's Surveyor 7 moon lander photographed a strange "horizon glow"
looking toward the daylight terminator. Observations are consistent with sunlight
scattered from electrically-charged moondust floating just above the lunar surface.
A Dusty Lunar Sky?
More possible evidence for dust came from the Apollo missions.
The Lunar Exosphere and Dust:
Sources & Sinks
Inputs:
Solar photons
Solar Energetic Particles
Solar wind
Meteoric influx
Large impacts
Dayside: UV-driven
photoemission, +10s V
Nightside: electron-driven
negative charging -1000s V
Processes:
Impact vaporization
Interior outgassing
Chemical/thermal release
Photon-stimulated desorption
Sputtering
Lunar Exosphere
Cold-trapping in
Polar regions
Formation of
Lunar volatiles
Mendillo et al, 1997
Stern, 1999;Smyth
and Marconi, 1995
Vondrak and
Crider, 2003
Exospheres and Dust
Surface Boundary Exospheres (SBEs)
may be the most common type of
atmosphere in the solar system…
Large
Asteroids &
KBOs
Mercury
Moon
Europa &
other Icy
satellites
Evidence of dust motion on
Eros and the Moon....
Io
Eros
Delory, American Geophysical Union Fall Meeting 12-16-09
LADEE
The Lunar Atmosphere and Dust Environment Explorer
•Determine the global density,
composition, and time variability of the
fragile lunar atmosphere before it is
perturbed by further human activity.
•Determine the size, charge, and spatial
distribution of electrostatically
transported dust grains.
•Test laser communication capabilities.
•Demonstrate a low-cost lunar mission:
• Simple multi-mission modular bus
design
• Low-cost launch vehicle
Neutral Mass Spectrometer (NMS)
UV Spectrometer (UVS)
MSL/SAM Heritage
LCROSS heritage
SMD - directed instrument
SMD - directed instrument
In situ
measurement of
exospheric
species
Dust and exosphere
measurements
P. Mahaffy
NASA GSFC
A. Colaprete
NASA ARC
150 Dalton range/unit mass resolution
Lunar Dust EXperiment (LDEX)
Lunar Laser Com Demo (LLCD)
HEOS 2, Galileo, Ulysses and Cassini Heritage
Technology demonstration
SMD - Competed instrument
High Data
Rate
Optical
Comm
SOMD - directed instrument
100 mm Optical
Module
s
D.
Boroson
MIT-LL
dem
Mo
ol
ntr
Co onics
ctr
Ele
60 c
m
M. Horányi, LASP
51-622 Mbps
Spacecraft Configuration
•330 kg spacecraft mass
•53 kg payload mass
LADEE Mission Profile
• Launch
in 2013 from Wallops as the
first payload to fly on the new
Minotaur V launch vehicle.
• 2-3 phasing orbits to get to Moon.
• Insertion into retrograde orbit
around Moon.
• Checkout orbit (initially 250km) for
30 days.
• 100-day science mission at ~2075km.
LADEE and Lunar Impacts
NASA Meteoroid Environment Office
Lunar Impact Monitoring Program
•Help lunar scientists determine the
rate of meteoroid impacts on the Moon.
•Meteoroid impacts are an important
source for the lunar exosphere and dust.
•Can be done with a telescope as small as
8 inches of aperture.
Also to working with AAVSO Lunar
Meteoritic Impact Search Section.
Provide Background Science Data: LADEE and Lunar Impacts
Confirmed Lunar Impact March 13, 2008 02:04:21UT by George Varos
Phase Matters
•Impact flashes are observed in the unilluminated area of the Moon.
•Near 1st Qtr, the Moon’s leading hemisphere faces Earth – generally best
for observing impact flashes.
•Near 3rd Qtr, the Moon’s trailing hemisphere faces Earth – generally less
favorable for observing impact flashes.
•A large gibbous phase results in lots of glare from illuminated lunar surface,
small unilluminated area for observing flashes, and diminished Earth shine
on unilluminated area making localizing impacts difficult.
•Thin crescent phase results in restricted observing time in dark sky.
Lunar Meteoroid Impact Monitoring
Minimum System Requirements
•8" telescope
~1m effective focal length
Equatorial mount or derotator
Tracking at lunar rate
•Astronomical video camera with adapter to fit telescope
NTSC or PAL
1/2" detector
•Digitizer - for digitizing video and creating a 720x480 .avi
Segment .avi to files less than 1GB (8000 frames)
•Time encoder/signal
GPS timestamp or WWV audio
•PC compatible computer
~500GB free disk space
•Software for detecting flashes
LunarScan software available as a free download
Meteor Counting
•The vast majority of meteoroids impacting the Moon are too small to be
observable from Earth.
•Small meteoroids encountering the Earth’s atmosphere can result in
readily-observable meteors.
•Conducting counts of meteors during the LADEE mission will allow us to
make inferences as to what is happening on the Moon at that time.
•Much more simple requirements: a dark sky, your eyes, and log sheet.
(a reclining lawn chair is very nice too!)
•International Meteor Organization (http://imo.net/)
•American Meteor Society (http://www.amsmeteors.org/)
Image credit:NASA/ISAS/Shinsuke Abe and Hajime Yano
Now for Android too!
Lunar Phases for Major Meteor Showers
During Projected LADEE Mission Timeframe
Aug 12 2013
Oct 21 2013
Nov 19 2013
Dec 14 2013
Dec 22 2013
Jan 4 2014
Perseids
Orionids
Leonids
Geminids
Ursids
Quadrantids
Waxing Crescent
Waning Gibbous
Waning Gibbous
Waxing Gibbous
Waning Gibbous
Waxing Crescent
Lunar Phase Aug 12, 2013
35%
90%
94%
95%
73%
13%
Radio Observations of Meteors
•Meteors produce a column of ionized gas as they pass through the
atmosphere.
•This column reflects radio waves from transmitters on Earth’s surface.
•The columns of ionized gas created by meteors usually last for only a
fraction of a second.
•Brighter meteors can produce columns that last for several seconds.
•Traditionally, VHF frequencies between 40-60 MHz have been used.
•Frequencies at low end of the FM band between 88-104 MHz are also
useful.
•Most radio systems used for meteor detection are of the forward scatter
type.
Radio Observations of Meteors
•Radio observations provide the only way to measure activity from
daytime meteor showers.
•Radio observations have fewer constraints imposed by clouds and light
pollution (both man-made and arising from fuller lunar phases).
•Observations are preferentially made in the hours proceeding from
midnight to noon.
Daytime Meteor Showers
Shower
Capricornids/Sagittariids
Chi Capricornids
April Piscids
Delta Piscids
Epsilon Arietids
May Arietids
Omicron Cetids
Arietids
Zeta Persieds
Beta Taurids
Gamma Leonids
Sextantids
Activity Period
1/15-2/4
1/29-2/28
4/8/-4/29
4/24-4/24
4/24-5/27
5/4-6/6
5/5-6/2
5/22-7/02
5/20-7/5
6/5-7/17
8/14-9/12
9/9-10/9
Maximum
2-Feb
14-Feb
20-Apr
24-Apr
9-May
16-May
20-May
7-Jun
9-Jun
28-Jun
25-Aug
27-Sep
Example: MSFC Forward Scatter Meteor Radar
•Antenna: 6-element Yagi; commercially available cut-to-frequency channel 4 TV
antenna
•Antenna orientation: Sits on the ground, pointed straight up
•Receiver: ICOM PCR-1000 receiver
•Receiver Settings: The CW demodulator is used so that 67.250 MHz (channel 4 zero
offset) appears at about 700 Hz. This also inverts the passband so that the doppler
shift of meteor echoes is reversed (frequency increases rather than decreases to the
'zero' frequency of the trail echo). The filter is set to 3 kHz bandwidth and the AGC is
turned off.
Example: MSFC Forward Scatter Meteor Radar
Local Channel 4 zero offset TV transmitters with a circle around each showing
the areas they illuminate down to an altitude of 100 km (typical meteor
altitude). Although the transmitters are over the horizon for MSFC on the
ground, a meteor at 100 km above MSFC has a direct line of sight. System
was detecting ~2,000 pings per day.
System Requirements
•General coverage radio receiver capable of tuning TV channels 2-6 (54-88
MHz) with CW or SSB demodulator
• Antenna Commercial TV antenna or build-it-yourself
•PC compatible computer w/sound card
•Required cabling
•Fast Fourier Transform and Meteor Counting Software
Receiver: The only real requirement is that you can tune to 54-88 MHz and
demodulate a SSB (single side band) or CW (continuous wave – or Morse code)
signal.
Antenna: A simple 2 element Yagi antenna provides the best gain/field of view
combination but have also used a higher gain 6 element cut-to-frequency
commercial TV antenna. A good compromise is a VHF or VHF/UHF multielement TV antenna like those available from Radio Shack.
Challenges
•Fewer appropriate VHF transmitters available with demise on
analog TV broadcasting.
•In many areas in the U.S., tuning to an empty frequency can be
challenging.
•Ideal VHF window for meteor detection of 25-60 MHz is being
impinged upon by increasing solar activity, with ionospheric
bounce increasing as exhibited by reflections up to and beyond 30
MHz.
PSK2k – A Meteor Scatter Solution?
•High speed meteor scatter software written by Klaus von der Heide (Hamburg
University).
•Instead of needing a TV transmitter or beacon, works with 2 or more amateurs
using mutual frequency and any suitable transceiver/PC/soundcard combination.
•Can be operated in fully automatic mode if required. This enables QSO’s to be
completed automatically without user intervention.
•Works with hardware commonly in use by amateurs.
•Provides an extra human element with collaboration between individuals.
Questions
•How usable is this software by visually-impaired operators?
•Are there alternative solutions we should be looking at?
Opportunities
•Gather data that could be useful to the LADEE mission and lunar science.
•Improve understanding of poorly characterized daytime meteor streams.
•Provide enhanced capabilities for U.S. participation in this area of research,
building upon experience of Japanese and Dutch networks.
•Leverage the interest in NASA space exploration to attract more people to amateur
radio.
•Excellent opportunity for student engagement.
•High-profile opportunity to engage students at the California School for the Blind
and members of the National Federation for the Blind.
Questions