It is possible there could be fossil life on Mars. This is an example that a one scientist recently said could be fossils of past life:
It doesn't look like much to most of us, but to a trained microbiologist, this is what she saw:
Follow up: Signs of Ancient Life in Mars Rover Photos? - Astrobiology Magazine
This is an example from Earth
After a lot of debate, was eventually confirmed to be an ancient stromatolite so created by microbes - clincher was through analysis of organics found in it. Stepping Stones through Time - Astrobiology Magazine
This however
is a desert rose - it is not created by any form of life but is more like a kind of a crystal in how it grows. File:Baryte-121038.jpg - Wikimedia Commons
Here are some salt crystals growing, again, if you didn't know the details of what it was, just judging by the form, you could mistake it for life
On the subject of fossils, and difficulty of telling if something on Mars is a fossil or not, this is a good site, though the material is from about a decade ago.
Mars Fossils, Pseudofossils or Problematica?
Including the spherules which often have necks attached to them:
And the ring shaped "Hallucogenia
See Some Objects Noticed in Martial Soil Images
The author. Michael Davidson, says
And he suggests searching in situ with instruments able to detect biological signatures.
See also "Avoiding the F word on Mars"
The problem is that on Earth - often after a lot of research, we now have a pretty good idea of what is a fossil and what isn't. With only occasional difficult borderline cases.
On Mars, we don't have that experience. It is possible that scientists ten or twenty years from now, with knowledge we don't have now, will be able to go through the images we have spotting all kinds of fossils. Or they might none of them be fossils.
It is just too soon to know yet. Mars is so very different from Earth in so many ways.
This is an example from Earth
This however
is a desert rose - it is not created by any form of life but is more like a kind of a crystal in how it grows. File:Baryte-121038.jpg - Wikimedia Commons
Here are some salt crystals growing, again, if you didn't know the details of what it was, just judging by the form, you could mistake it for life
On the subject of fossils, and difficulty of telling if something on Mars is a fossil or not, this is a good site, though the material is from about a decade ago.
Mars Fossils, Pseudofossils or Problematica?
Including the spherules which often have necks attached to them:
And the ring shaped "Hallucogenia
See Some Objects Noticed in Martial Soil Images
The author. Michael Davidson, says
"But nothing is certain and all the evidence is still ambiguous. The author is probably more skeptical about these being real biogenic fossils than most. He is perplexed by the dimples on the spherules and would assign the spherules maybe a 3 percent chance of being organically formed. His proposed microbial or algae mat has maybe a 4 percent chance of being organic.The exo-corals, and the exo-cephalopods, the rotinis and other vug objects should, almost certainly, be explained using non-biological processes. Corals and worms are organisms too evolutionarily advanced to hope for the small window of life that Mars had open. However, the importance of finding fossils on Mars is so momentous that, even with these unlikely odds, the possibility should be explored thoroughly."
See Mars Fossils, Pseudofossils or Problematica
And he suggests searching in situ with instruments able to detect biological signatures.
See also "Avoiding the F word on Mars"
The problem is that on Earth - often after a lot of research, we now have a pretty good idea of what is a fossil and what isn't. With only occasional difficult borderline cases.
On Mars, we don't have that experience. It is possible that scientists ten or twenty years from now, with knowledge we don't have now, will be able to go through the images we have spotting all kinds of fossils. Or they might none of them be fossils.
It is just too soon to know yet. Mars is so very different from Earth in so many ways.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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