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Martian "microfossils" in lunar meteorites?
1Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville 72701, USA. cosmo@uafsysb,uark.edu
Meteoritics & Planetary Science
|September 7, 2001
Summary
Microscopic structures found in lunar meteorites resemble those claimed as microfossils in Martian meteorites. This suggests these forms, including nanobacteria, may originate from terrestrial contamination, not extraterrestrial life.
Area of Science:
- Astrobiology
- Geology
- Meteoritics
Background:
- McKay et al. (1996) proposed evidence for relic life in Martian meteorite ALH 84001, including microfossil-like objects.
- These objects were described as ovoid and elongated forms, similar to terrestrial nanobacteria.
Purpose of the Study:
- To investigate the origin of microfossil-like structures found in meteorites.
- To determine if similar structures exist in non-Martian meteorites with a shared terrestrial history.
Main Methods:
- Replication of McKay et al.'s (1996) procedures and apparatus.
- Examination of internal fracture surfaces of lunar meteorites.
Main Results:
- Structures indistinguishable from those in ALH 84001 were found on lunar meteorite surfaces.
- Lunar surface is considered a sterile environment.
Conclusions:
- The presence of similar structures on lunar meteorites suggests a non-Martian origin.
- Terrestrial contamination, possibly from Antarctic weathering, is a plausible source for these forms.
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