Perseverance ha scoperto una roccia, soprannominata “Cheyava Falls”, che potrebbe aver ospitato vita microbica miliardi di anni fa.
“Cheyava Falls is the most puzzling, complex, and potentially important rock yet investigated by Perseverance,” said Ken Farley, Perseverance project scientist of Caltech in Pasadena. “On the one hand, we have our first compelling detection of organic material, distinctive colorful spots indicative of chemical reactions that microbial life could use as an energy source, and clear evidence that water — necessary for life — once passed through the rock. On the other hand, we have been unable to determine exactly how the rock formed and to what extent nearby rocks may have heated Cheyava Falls and contributed to these features.”
Un breve video che descrive la scoperta.
Edit 26/07.
Il selfie nei pressi di “Cheyava Falls"
Mastcam-Z Views ‘Leopard Spots’
The spots seen in the rock are small, irregularly shaped light patches surrounded by a thin rim of dark minerals. These spots indicate chemical conditions during formation or alteration of this rock billions of years ago that could have provided energy for microbial life, if it was ever present at this location on Mars.
Edit 28.07
Thread lungo e interessante di Mike Malaska, chimico organico e astrobiologo al JPL sulla rilevanza di questa scoperta.
[…] That sample is really interesting. In the big scheme of looking for life on other worlds, this is a good start point.
It looks like there is a redox zonation around some grains. That means that at some point there was enough chemical energy for materials to “swap electrons and do chemical things.”
Life is famous for sometimes, not always, being the middleman in those chemical reactions. Harvest that energy and use it for for “life things.”
Do you always have to have a visible redox couple? No. sometimes it can be so small or trace that you miss it. Could be even below instrument detection limits. (Trace gas metabolism can be operating at ppm levels)
But having a visible redox rind is definitely a “nice to have” indicator. If I was wandering around looking for rocks that might indicate life, this would be something I would want to look at closer. […]
Inizia qui:
Edit 29.07
Approfondimento su The Conversation, Sean McMahon , Astrobiology, University of Edinburgh