Are micro-organisms fossils on so-called Martian meteorite true?

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No confirmed Martian fossils exist, despite intriguing evidence from the SNC meteorites, particularly the ALH84001 specimen. Researchers from Stanford University and NASA's Johnson Space Flight Center reported potential signs of ancient bacteria-like life forms, including polycyclic aromatic hydrocarbons (PAHs) and carbonate globules, analyzed using scanning electron microscopy and laser mass spectroscopy. However, these findings are not definitive proof of past life on Mars and require further validation. The discussion emphasizes the importance of rigorous scrutiny before concluding the existence of extraterrestrial life.

PREREQUISITES
  • Understanding of SNC meteorites and their significance in astrobiology.
  • Familiarity with scanning electron microscopy and laser mass spectroscopy techniques.
  • Knowledge of polycyclic aromatic hydrocarbons (PAHs) and their association with biological activity.
  • Awareness of the historical context surrounding the ALH84001 meteorite findings.
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  • Research the latest findings on Martian meteorites and their implications for astrobiology.
  • Study the methods of scanning electron microscopy and laser mass spectroscopy in detail.
  • Explore the significance of polycyclic aromatic hydrocarbons (PAHs) in geological and biological contexts.
  • Investigate the history and analysis of the Viking lander soil samples and their implications for organic material detection.
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Astronomers, astrobiologists, planetary scientists, and anyone interested in the search for extraterrestrial life and the analysis of Martian meteorites.

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Are micro-organisms fossils on so-called Martian meteorite true? I think it is more likely contaminated by life on Earth...
 
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Are you talking about the SNC meteorites?

In short, no Martian fossils have been confirmed, but there are some interesting leads.

http://scienceworld.wolfram.com/astronomy/SNCMeteorites.html

Interest in SNC meteorites was recently rekindled by the announcement from researchers at Stanford University and NASA's Johnson Space Flight Center that careful analysis of the ALH84001 meteorite had yielded evidence of ancient bacteria-like life forms on Mars. This work was set to appear in an issue of the journal Science but was leaked to the press on August 6, 1996. The resulting surge of interest led to a NASA press release on Aug. 7, 1996 followed by a press conference. The resulting tumult precipitated a flurry of media and NASA public relations activity which included a front-page story in The New York Times (Wilford 1996).

Using scanning electron microscopy and laser mass spectroscopy, a team led by David S. McKay identified polycyclic aromatic hydrocarbons (PAHs) in the meteorite, as well as globules of carbonate and the minerals magnetite and iron sulfide. The carbonate globules are small elongated features resembling similar ones found on Earth which are believed to have formed in association with bacteria. McKay et al. (1996) determined their age to be approximately 3.6 billion years. All the unusual compounds found in the meteorite are associated with bacterial activity on Earth, PAHs with decay products of microorganisms and magnetite and iron sulfide with anaerobic bacteria. However, the presence of these compounds is not necessarily diagnostic for the presence of bacteria. McKay and his coworkers appear to have excluded the possibility that any of their discoveries represent terrestrial contamination, so the constituents they describe presumably must have formed while the meteorite was still on the surface (or shallow subsurface) of Mars.
While the reported discoveries are intriguing and consistent with formation through biological activity (especially when taken together), this conclusion requires additional confirmation. It should be recalled that initial experiments on soil samples from one of the Viking landers were heralded as clear evidence of organic material, whereas subsequent laboratory work showed that the observed results could be reproduced with entirely inorganic soil constituents. While the presence of past life on Mars would be a scientific discovery of epic proportions and warrants the closest possible scrutiny, it is premature at this juncture to state that the existence of life on Mars, past or present, has been conclusively demonstrated.
 
There are 32 meteorite specimens currently believed to originate from mars. List is here:
http://www2.jpl.nasa.gov/snc/
Meteorite ALH84001 was thought to show evidence of life. The results are considered inconclusive to date AFAIK.
 

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