Transcript History of Mars Exploration, Part 2 – Viking thru Mars Pathfinder

Early Spacecraft Exploration
Viking
 “The scientific goal of the Viking missions is to ‘increase
our knowledge of the planet Mars with an emphasis on the
search for extra-terrestrial life.’ The scientific questions
deal with the atmosphere, the surface, the planetary body,
and the question of bio-organic evolution.”
Viking Press Kit, July 1975
Early Spacecraft Exploration
Viking
Get down, get dirty.
Twin orbiter/lander combos
Early Spacecraft Exploration
Viking
 V1 devoted the first month to searching for landing sites
for the lander; V1 lander touched down July 20, 1976 in
Chryse Planitia
 V2 first month devoted to searching for a landing site; V2
touched down September 3, 1976 in Utopia Planitia
Early Spacecraft Exploration
Viking
 V1 devoted the first month to searching for landing sites
for the lander; V1 lander touched down July 20, 1976 in
Chryse Planitia
 V2 first month devoted to searching for a landing site; V2
touched down September 3, 1976 in Utopia Planitia
 Delayed landing…
Early Spacecraft Exploration
Viking
 V1 devoted the first month to searching for landing sites
for the lander; V1 lander touched down July 20, 1976 in
Chryse Planitia
 V2 first month devoted to searching for a landing site; V2
touched down September 3, 1976 in Utopia Planitia
 Delayed landing…
 Landing sites selected with Mariner 9 imagery, Viking
orbiter cameras were higher resolution
Early Spacecraft Exploration
Viking
 Landing Site Locations
Early Spacecraft Exploration
Viking
 With landers on the ground, orbiters continued science
mission above and acted as data relays for landers
Early Spacecraft Exploration
Viking
Sinuous canyon in
Nanedi Vallis
Early Spacecraft Exploration
Viking
Early Spacecraft Exploration
Viking
Early Spacecraft Exploration
Viking
Viking 2 lander touched down
with one pad on a boulder;
tilted 8°.
Early Spacecraft Exploration
Viking
Early Spacecraft Exploration
Viking
 Notable results from Viking orbiters:
 Mapped 97% of the surface; 52,000 total images
 Definitively determined the North residual polar cap is
water-ice, not frozen carbon dioxide
 Stirred up a little “controversy” with one particular image
Early Spacecraft Exploration
Viking
Early Spacecraft Exploration
Viking
 Notable results from Viking landers:
 Biology experiments provided no clear evidence for the presence of
living organisms in soil near the landing sites
 Gas Chromatograph/Mass Spectrometer found no evidence of
organic material at either landing site
 Winds blew more slowly than anticipated (200 MPH); highest
recorded wind gust was 120 km/hr (74 mph) and average velocities
were much lower
 Weather in the Martian midsummer was repetitious but was
variable and more interesting in other seasons
Early Spacecraft Exploration
Viking
 Notable results from Viking
landers:
 Atmospheric composition:
 CO2: 95.32%
 N: 2.7%
 Ar: 1.6%
 O: 0.13
 CO: 0.7%
 H2O (vapor): 0.03%
Early Spacecraft Exploration
Viking
 Notable results from Viking
landers:
 Atmospheric composition:
 CO2: 95.32%
 N: 2.7%
 Ar: 1.6%
 O: 0.13
 CO: 0.7%
 H2O (vapor): 0.03%
 1963:
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72% N2
25% CO2
2% Ar
< 0.5% O2
Trace amounts of H2O
Early Spacecraft Exploration
Viking
 How did Viking advance scientific understanding of Mars?
 Difficult for life to exist on the surface at present, but this does not rule out
past life
 More evidence for past habitability
 Weather patterns
 Though no current life, Mars is a dynamic planet
 What technological advance(s) did Viking carry?
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LANDER!!
Higher res. Cameras
Weather station
Biology experiments
Orbiters acted as communications relay, selective landing sites
Early Exploration
How did Viking change and/or reaffirm perceptions
of Mars?
History of Mars Exploration
 Viking mission operations ended in the early 1980s
 Viking missions gave scientists the most complete picture
of Mars to date
History of Mars Exploration
 Attempts to explore Mars did not start up again until the
early 1990s. Why not?
 Why was it revived?
History of Mars Exploration
 Attempts to explore Mars did not start up again until the
early 1990s. Why not?
 Why was it revived?
History of Mars Exploration
 Attempts to explore Mars did not start up again until the
early 1990s.
 The first one failed.
 The next two gave Mars a face-lift and showed a new way
to explore.
Modern Exploration
Global Surveyor
Modern Exploration
Global Surveyor
 Objectives:
 High resolution imaging of the surface
 Study the topography and gravity
 Study the role of water and dust on the
surface and in the atmosphere
 Study the weather and climate of Mars
 Study the composition of the surface and
atmosphere
 Study the existence and evolution of the
Martian magnetic field
Modern Exploration
Global Surveyor
Credit: Malin Space Science Systems – www.msss.com
Credit: Malin Space Science Systems – www.msss.com
Modern Exploration
Global Surveyor
Modern Exploration
Global Surveyor
 Notable results from Global Surveyor
 The northern hemisphere is probably just as cratered as the
southern hemisphere, but the craters are mostly buried.
 High-resolution imagery shows modifications to the surface
have taken place over the past decade.
 Hundreds of gullies were discovered that were formed from
liquid water (probably), possibly in recent times.
 The Thermal Emission Spectrometer found that just about all
of the surface of Mars is covered with volcanic rock.
 Magnetometer data show remnant, alternating magnetic
fields
Modern Exploration
Global Surveyor
 How did Global Surveyor advance scientific understanding
of Mars?
 Smoking gun evidence that liquid water was stable on the
surface for long periods of time
 Mars exhibits a “global dichotomy” in terms of topography
 Spectral ID of the global surface composition
 What technological advance(s) did Global Surveyor carry?
 Highest-resolution camera, for the time
 Laser altimeter
 TES; lithology, mineralogy
 Magnetometer; remnant magnetic field
Early Exploration
How did Mars Global Surveyor change and/or
reaffirm perceptions of Mars?
Modern Exploration
Mars Pathfinder
Modern Exploration
Mars Pathfinder
 The primary mission objectives were to demonstrate the
feasibility of low-cost landings on, and exploration of, the
Martian surface (Faster, Better, Cheaper)
 Scientific objectives included
 atmospheric entry science
 long-range and close-up surface imaging
 the general objective was to characterize the Martian environment
for further exploration
Modern Exploration
Mars Pathfinder
 Landed in Ares Vallis which was believed to be the site of
an ancient flood
 Landing site selection made using Viking orbiter imagery
 First rover; first to use airbags
Modern Exploration
Mars Pathfinder
 Landing Site Locations
Modern Exploration
Mars Pathfinder
 Pathfinder Landing Site
Modern Exploration
Mars Pathfinder
 Pathfinder Landing Site
Modern Exploration
Mars Pathfinder
 Notable results from Pathfinder
 More than 16,500 images from the lander and 550
images from the rover
 More than 15 chemical analyses of rocks and soil and
extensive data on winds and other weather factors
 Findings from the investigations carried out by scientific
instruments on both the lander and the rover suggest
that Mars was at one time in its past warm and wet, with
water existing in its liquid state and a thicker
atmosphere
Modern Exploration
Mars Pathfinder
 How did Pathfinder advance scientific understanding of
Mars?
 Evidence on the ground for a warm, wet past
 What technological advance(s) did Pathfinder carry?
 First rover; can be remotely operated
 New landing system
Early Exploration
How did Mars Pathfinder change and/or reaffirm
perceptions of Mars?