NASA Discovers ‘Clearest Sign’ Yet of Ancient Life on Mars in a Rock Studied by the Perseverance Rover
Minerals in the rock might have been produced by microbes in chemical reactions, but researchers say they’ll need to examine the sample more closely to know for sure
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A rock sampled by NASA’s Perseverance rover from an ancient, dry riverbed on Mars may contain signs of life, according to a new study.
The sample was taken in July 2024 from an arrowhead-shaped rock called Cheyava Falls, located along the edge of Neretva Vallis, an ancient river valley within the Jezero Crater. As soon as Perseverance spotted the rock, it looked exciting to scientists—it had several features that suggested possible signatures of microbial life. Now, the team’s further research suggests their initial excitement was well-earned.
“After a year of review, they have come back and they said, listen, we can’t find another explanation,” Sean Duffy, acting administrator of NASA, said at a news briefing on Wednesday, per CNN’s Ashley Strickland. “So, this very well could be the clearest sign of life that we’ve ever found on Mars, which is incredibly exciting.”
Still, the findings are not a confirmation of life. “With the publication of this peer-reviewed result, NASA makes this data available to the wider science community for further study to confirm or refute its biological potential,” Nicky Fox, associate administrator for NASA’s science mission directorate, says in a statement.
Key concept: What is Cheyava Falls?
Cheyava Falls is a reddish rock sampled by NASA’s Perseverance rover in Jezero Crater on Mars last year. Scientists say it contains minerals that could be signs of chemical reactions produced by past microbial life.
Long ago, water flowed at the sampled site on Mars. And NASA scientists determined the Cheyava Falls rock is rich in chemical compounds that could have once supported life. They found organic carbon, sulfur, phosphorus and oxidized iron, or rust.
Various markings on the rock suggested microbes might have once converted those materials into energy. High-resolution images showed “leopard spots”—lighter specks surrounded by dark rings—containing the signatures of the minerals vivianite and greigite. On Earth, vivianite (hydrated iron phosphate) is often found near decaying organic matter and in sediments, while some forms of microbial life can produce greigite (iron sulfide). Other markings, dubbed “poppy seeds” because of their smaller size, also contain vivianite.
“These would be examples of microbially influenced environments where the microbes are consuming the organic matter and making these minerals as a byproduct,” Joel Hurowitz, a Perseverance scientist and researcher at Stony Brook University, tells Kenneth Chang at the New York Times.
The findings were published in the journal Nature on Wednesday.
There are, however, non-biological ways these minerals can be produced, including at extremely high temperatures or in acidic conditions. But the sample doesn’t show any evidence of either of those scenarios being the case, and it’s unclear if the minerals could have formed at low temperatures. “Within the sort of limitations of our rover payload capabilities, they don’t look like they’ve been cooked,” Hurowitz adds to the New York Times.
The next step for the researchers is to continue their analysis in laboratories on Earth—which means they would need to bring the sample here. Exactly how or when that might happen, however, hangs in the air. President Trump’s proposed budget would cancel NASA’s Mars Sample Return mission, reports Reuters’ Will Dunham.
“We believe there’s a better way to do this, a faster way to get these samples back,” Duffy said at the news conference, per Bill Chappell at NPR. The New York Times notes Duffy did not provide specific details about an alternative mission. China has also proposed plans for a Mars sample return mission that could launch in 2028.
“Bringing this sample back to Earth would allow us to analyze it with instruments far more sensitive than anything we can send to Mars,” says study co-author Michael Tice, a geologist at Texas A&M University, in a statement. “What’s fascinating is how life may have been making use of some of the same processes on Earth and Mars at around the same time… It’s a special and spectacular thing to be able to see them like this on another planet.”
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