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 and get dirty.
Early Spacecraft Exploration
Viking
 The primary mission objectives were to:
 Obtain high resolution images of the Martian surface
 Characterize the structure and composition of the
atmosphere and surface and
 Search for evidence of life
Twin orbiter/lander combo
Early Spacecraft Exploration
Viking
 Orbiter instruments
 Visual Imaging Subsystem – two cameras (124 ft/px); could
resolve objects the size of a football field
 IR Thermal (temperature) Mapper
 Mars Atmospheric Water Detector
 “Again a question: Are we now seeing the last disappearing
remnants of water that was once much more plentiful on the
planet, or is Mars locked in an ice age that has frozen out most of
its water in the polar caps or beneath a layer of surface dust?”
Early Spacecraft Exploration
Viking
 Lander instruments
 Two panoramic cameras
 Sampler arm
 Meteorology boom w/ temperature, wind direction and
velocity sensors
 Seismometer
 Biology experiment
 Gas chromatograph mass spectrometer
 X-ray fluorescence spectrometer
 More info on each instrument can be found at:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/197
50018961_1975018961.pdf
Early Spacecraft Exploration
Viking
 V1 Launched August 20, 1975; arrived at Mars June 19,
1976
 Devoted first month to searching for landing sites for the
lander; V1 lander touched down July 20, 1976 in Chryse
Planitia
Early Spacecraft Exploration
Viking
 V2 launched September 9, 1975, arrived at Mars on
August 7, 1976
 First month devoted to searching for a landing site; V2
touched down September 3, 1976 in Utopia Planitia
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
 DATA!!
Early Spacecraft Exploration
Viking
•
•
•
•
•
•
•
How would you rate the quality of these images?
What observations can you make?
How would you interpret these observations?
What can you say we know about Mars at this
point? How certain are you?
What questions would you ask about Mars?
How would you attempt to answer these questions?
What are the limitations to this type of mission
(spacecraft/instruments)?
Early Spacecraft Exploration
Viking
Sinuous canyon in
Nanedi Vallis
Early Spacecraft Exploration
Viking
Large outflow channel originating at
chaotic terrain.
Early Spacecraft Exploration
Viking
Stream-lined Islands in
Ares Vallis
Early Spacecraft Exploration
Viking
Dendritic Drainage
Network
Early Spacecraft Exploration
Viking
Channel in Ares Vallis; 25km
(~16 miles) wide, 1km (~0.6
miles) deep
Early Spacecraft Exploration
Viking
Ma'adim Vallis (~300km; ~186 miles) runs north and
terminates into Gusev Crater (right).
Early Spacecraft Exploration
Viking
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
 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
 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?





LANDER!!
Higher res. Cameras
Weather station
Biology experiments
Orbiters acted as communications relay, selective landing sites