Transcript Document

Welcome to
Starry Monday at Otterbein
Astronomy Lecture Series
-every first Monday of the monthNovember 5, 2007
Dr. Uwe Trittmann
Today’s Topics
• Recent Advances in Astronomy Introduction
• The Night Sky in November
Feedback!
• Please write down suggestions/your interests on the
note pads provided
• If you would like to hear from us, please leave your
email / address
• To learn more about astronomy and physics at
Otterbein, please visit
– http://www.otterbein.edu/dept/PHYS/weitkamp.asp (Obs.)
– http://www.otterbein.edu/dept/PHYS/ (Physics Dept.)
Recent Advances in Astronomy
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Data
Theory
Instruments
Space Flight
Space probes
Introduction
• In the last 15 years cosmology has become a (very) exact science
– 1970ies: Age of the universe is 10-20 billion yrs
– Now: the universe is 13.7±0.1 billion years old
• Eagerly anticipated results have been obtained
– “Temperature” of the universe is 2.725 K, isotropic 1 part in 100,000
• Unexpected discoveries occurred
– Acceleration of cosmological expansion
– The universe contains strange & unknown stuff
• Changing of space exploration agencies
– Commercial spaceflight
– China, Japan, India
– Bush’s Moon-Mars initiative changes NASA’s objectives
• Instrumentation has improved dramatically
– CCD cameras
– Adaptive optics
• New “Astronomies”
– Neutrino, X-ray, IR, ...
Recent Advances in Astronomy:
Space Probes
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Cassini / Huygens
Chandra
Mars Rovers
WMAP
Galileo
Hayabusa
Deep Impact
Many more …
Deep Impact –
The Comet
Crasher
Comet Impact:
July 4, 2005
Impact Velocity:
23,000 mph
Spacecraft Size:
Flyby spacecraft - nearly as
large as a Volkswagen
Beetle automobile.
Impactor spacecraft - about
the same dimensions as a
typical living room coffee
table.
Comets - Traveling Dirty Snowballs
• Small icy bodies, “dirty snowballs”
• Develops a “tail” as it approaches the Sun
Comet Anatomy
• Tail may be up to 1 A.U. long
Halley’s Comet – Now and then
• Halley’s Comet in 1910
• Top: May 10, 30° tail
• Bottom May 12, 40° tail
• Halley’s Comet in 1986
• March 14, 1986
Comet Shoemaker-Levy 9
• HST image (1994); Earth added to show scale
Comet Shoemaker-Levy 9
Headed for Jupiter…
Impact on Jupiter
Deep Impact –
The Comet
Crasher
Comet Impact:
July 4, 2005
Impact Velocity:
23,000 mph
Spacecraft Size:
Flyby spacecraft - nearly as
large as a Volkswagen
Beetle automobile.
Impactor spacecraft - about
the same dimensions as a
typical living room coffee
table.
Temple 1 Coordinate System
“Deep Impact”
crashes into comet
Temple 1
This is how a comet
looks like!
Viewed from the
flyby spacecraft
from Hubble Space Telescope
• Spirit at Gusev Crater
– Sol: 1365 Time: 21:18
– Sols past warranty: 1275
• Opportunity at Meridiani Sinus
– Sol: 1345 Time: 9:17
– Sols past warranty: 1255
Martian Surface
Iron gives the characteristic Mars color: rusty red!
View of Viking 1
1 m rock
Sojourner
Martian Panorama
Note: the sky is not black as on the moon,
but pale pink of the dust in the atmosphere!
“Twin Peaks” – about 1-2 km away
Mars Panorama: Opportunity has
landed!
Landing Sites
A couple of 1000 miles apart!
Meteorite ALH 84001
• Discovered in
Antarctica in 1984
– 2 kg, 17 cm across
• Chemical analysis
indicates it came from
Mars
• In 1996, a team of
scientists argued that it
contains fossilized
evidence of bacteria that
came from Mars
Cassini/ Huygens
• Spectacular data from Saturn, Titan, and the Rings
Titan
• Titan is the only moon in the solar system
known to have an atmosphere
Infrared picture shows surface details
Titan from Cassini
Haze and
Atmosphere
Methane Clouds
False Colored Image
Map of Titan
Methane Rain & Lakes
Huygens sees Shoreline descending
SOHO
The Solar and
Heliospheric Observatory
(SOHO) monitors the Sun
(launched 1995). It
provides crucial early
warnings of impending
space weather that can
destroy satellites and
knock out power grids.
Scientists credit SOHO
with allowing forecasts
that prevent damage and
losses that might otherwise
occur.
Erupting prominence
Hubble Space
Telescope
• Launched 1993
• Above the
atmosphere
• 2.4m Mirror
HST: Planets
Hubble
Ultra
Deep
Field
HST: M51 Spiral Galaxy
The Night Sky in November
• The sun is past autumn equinox -> longer nights!
• Autumn constellations are coming up: Cassiopeia,
Pegasus, Perseus, Andromeda, Pisces
 lots of open star clusters!
• Mars is visible later at night
Moon Phases
• Today (Waning Crescent)
• 11/ 9 (New Moon)
• 11 / 17 (First Quarter Moon)
• 11 / 24 (Full Moon)
• (Last Quarter Moon)
Today
at
Noon
Sun at
meridian,
i.e.
exactly
south
10 PM
Typical
observing
hour,
early
October
Mars
Uranus
Neptune
Star
Maps
Celestial
North Pole –
everything
turns around
this point
Zenith – the
point right
above you &
the middle of
the map
40º
90º
West
The summer
triangle
lingers on
…
Due
North
Big Dipper
points to the
north pole
High up – the
Autumn
Constellations
• W of
Cassiopeia
• Big Square
of Pegasus
• Andromeda
Galaxy
Andromeda
Galaxy
• “PR” Foto
• Actual look
SouthEast
Perseus,
Auriga &
Taurus
with Plejades
and the
Double
Cluster
SouthWest –
2006
• Planets
– Uranus
– Neptune
• Zodiac:
– Capricorn
– Aquarius
SouthWest –
2007
• Planets
– Uranus
– Neptune
• Zodiac:
– Capricorn
– Aquarius
Mark your Calendars!
• Next Starry Monday: February 4, 2008, 7 pm
(this is a Monday
• Observing at Prairie Oaks Metro Park:
– Friday, November 16, 6:30 pm
– Friday, January 11, 6:00 pm
– Friday, February 15, 6:30 pm
• Web pages:
– http://www.otterbein.edu/dept/PHYS/weitkamp.asp (Obs.)
– http://www.otterbein.edu/dept/PHYS/ (Physics Dept.)
)
Mark your Calendars II
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Physics Coffee is every Wednesday, 3:30 pm
Open to the public, everyone welcome!
Location: across the hall, Science 256
Free coffee, cookies, etc.