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The Case for Extant Life on Mars and Its Possible Detection by the Viking Labeled Release Experiment
Gilbert V Levin1, Patricia Ann Straat2
11 Arizona State University , Tempe, Arizona.
Astrobiology
|September 15, 2016
Summary
The 1976 Viking Labeled Release experiment indicated microbial life on Mars, but this remains controversial. Recent data on Martian water, methane, and organics suggest extant life is a strong possibility.
Area of Science:
- Astrobiology
- Planetary Science
- Extraterrestrial Life Research
Background:
- The 1976 Viking Labeled Release (LR) experiment yielded positive results suggesting extant microbial life on Mars.
- These findings were controversial, with many attributing the results to nonbiological oxidants in Martian soil.
- Subsequent missions focused on Mars's habitability, gathering data on water, methane, and organics.
Purpose of the Study:
- To evaluate recent findings on Martian water, methane, and organics in the context of extant life.
- To reassess the biological explanation of the Viking LR experiment against nonbiological hypotheses.
- To consider the unique value of the LR data from pristine Martian samples.
Main Methods:
- Review of recent data on Martian environmental conditions (water, methane, organics).
- Comparative analysis of biological and nonbiological interpretations of the Viking LR experiment.
- Assessment of hypotheses regarding oxidants in Martian soil.
Main Results:
- Recent findings strengthen the possibility of extant life on Mars.
- Nonbiological explanations for the LR experiment's results are not conclusive.
- The LR data represent a unique dataset from a biologically pristine Mars.
Conclusions:
- Extant life on Mars remains a strong possibility.
- The Viking LR experiment's results warrant continued consideration of a biological explanation.
- Future research should consider the implications of potential terrestrial contamination on Martian samples.
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