Early Exploration Viking

1. Early ExplorationViking • “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

2. Early ExplorationViking Get down and get dirty.

3. Early ExplorationViking • 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

4. Early ExplorationViking • Orbiter instruments • Visual Imaging Subsystem – two cameras; each a telescope with a camera head (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?”

5. Early ExplorationViking • 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/19750018961_1975018961.pdf

6. Early ExplorationViking • 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 ChrysePlanitia

7. Early ExplorationViking • 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 • One leg landed on a rock; tilted 8.2°

8. Early ExplorationViking • With landers on the ground, orbiters continued science mission above and acted as data relays for landers

9. Early ExplorationViking • 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 • Atmospheric pressure varies by 30% during the Martian year due to sublimation and condensing of CO2 at the poles • Stirred up a little “controversy” with one particular image

10. Early ExplorationViking

11. Early ExplorationViking • 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

12. Early ExplorationViking • 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 • Orbiter comms. relay, selective landing sites