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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Possible surface reactions on Mars: implications for viking biology results
Science (New York, N.Y.)
|July 29, 1977
Summary
Simulations suggest Viking lander biology experiments
Area of Science:
- Astrobiology
- Planetary Science
- Chemistry
Background:
- The Viking Mars landers conducted three biology experiments to detect life.
- Two experiments, labeled release and gas exchange, yielded results that were initially interpreted as potentially biological.
Purpose of the Study:
- To simulate and re-evaluate the results of two Viking biology experiments.
- To determine if non-biological chemical reactions could explain the experimental outcomes.
Main Methods:
- Simulated the Martian surface and atmosphere.
- Used carbon-14 labeled organic compounds and ultraviolet light for the labeled release experiment simulation.
- Simulated the reaction of metal peroxides/superoxides with water for the gas exchange experiment.
Main Results:
- Simulations replicated the release of carbon-14 labeled carbon dioxide in the labeled release experiment.
- Simulations replicated the release of oxygen in the gas exchange experiment.
- Both experiments' results were explained by simulated abiotic reactions.
Conclusions:
- The results of the Viking labeled release and gas exchange experiments can be explained by non-biological chemical reactions.
- These findings suggest that the Martian surface and atmosphere chemistry could account for the observed Viking experiment data.
- Further investigation into abiotic processes is warranted for interpreting extraterrestrial life detection experiments.
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