NASA Says It's Found 'Clearest Sign' Yet of Past Life on Mars

Unusual rocks discovered on Mars contain the most tantalising evidence yet of potential past life on the Red Planet.

Credit: NASA/JPL

The mudstones, found in a dusty riverbed by NASA's Perseverance Rover, are dotted with intriguing markings nicknamed leopard spots and poppy seeds. Scientists believe these features contain minerals produced by chemical reactions that could be associated with ancient Martian microbes, reports the BBC.

It's possible the minerals were produced by natural geological processes, but at a press conference NASA said the features could be the clearest signs of life ever found.

Live Science reports that an initial analysis of the rock, which appeared in a lake bed formation known as Bright Angel, revealed it was crammed with organic compounds, had evidence that water once flowed through it, and contained flecks of leopard-like spots from chemical reactions that ancient microbes could have used for energy.

These features may result from non-biological processes occurring over millions of years. But now, in a new study published in the journal Nature, NASA scientists have announced intriguing details about additional rock samples found at two nearby sites - and they say these clues bolster the case for past life on Mars.

"After a year of review, they have come back and they said, listen, we can't find another explanation," Acting NASA Administrator Sean Duffy, said during a news briefing following the announcement. "So this very well could be the clearest sign of life that we've ever found on Mars, which is incredibly exciting."