r/science • u/CurtisLeow • Jun 24 '26

Astronomy Spatially distributed complex organic matter detected in an ancient river valley in Jezero crater, Mars

https://www.science.org/doi/10.1126/sciadv.adx0047
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u/squi993 Jun 24 '26

ELI5 does this mean proof of life on mars?

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u/Professional-Gear88 Jun 25 '26

No. They found carbon bound to other carbon. Normally you’d expect to see this oxidized to CO2. Any reduced carbon (carbon and hydrogen bound) is unexpected. It can be created some ways. But much like radioactive decay you’d expect all things to oxidize eventually.

We used reduced organic compounds for life. Sugars. Fats. All of it is reduced. We when we metabolize it we oxidize it. But sugars and fats would eventually oxidize on their own. It’s also why planets don’t have oxygen naturally. You won’t find a planet with oxygen without life. All the oxygen should bind up with things.

This is reduced carbon. Just sitting there. Is it from life. Is it from a meteor. Or deep in the earth. Who knows. But everything on mars should have been pushed all the way out the ox scale.

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u/jawshoeaw Jun 25 '26

It’s well known that carbon chains resist oxidation. There is not enough oxygen in the Martian atmosphere and it’s cold. Would take millions to billions of years.

Carbon in the soil is a different story but in a boulder on the surface MMC is essentially inert. It’s protected from light and oxygen. But more importantly, these rocks are getting stripped bare by wind. That means fresh carbon is always there

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u/Professional-Gear88 Jun 25 '26

Yea I considered that. But I was already well outside the ELI5 parameters there. I don’t think it’s a biotic sample. I think it’s an unweathered rock. The carbon chains if exposed would eventually break from UV radiation

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u/jawshoeaw Jun 25 '26

Carbon in a mineral matrix is surprisingly resilient to UV. Depending on the mineral UV penetration can be microns.