NASA just announced that its Perseverance rover recently found some promising signs of ancient life on Mars. The rover obtained a sample of rock formed billions of years ago from sediment and there are biomarkers indicating the potential presence of microbes once upon a time.
Basically, the rocks contain minerals that typically form as a result of a chemical reaction between mud and organic matter. That doesn’t necessarily mean that Mars once had life, as the minerals can form due to nonbiological processors. However, it’s certainly one of the best pieces of evidence we have to point toward our neighbor planet once housing life of some kind.
“On Earth, reactions like these, which combine organic matter and chemical compounds in mud to form new minerals like vivianite and greigite, are often driven by the activity of microbes,” said Stony Brook University planetary scientist Joel Hurowitz, who led the study published in the journal Nature. “The microbes are consuming the organic matter in these settings and producing these new minerals as a byproduct of their metabolism.”
Hurowitz does caution that this is just a potential biosignature and not actual proof of ancient life. Many scientists believe, however, that Mars wasn’t always quite as inhospitable as it is today.
The planet likely held plenty of water in its distant past. Researchers suggest that the area in which Persevere found these samples was once a river valley that led to a lake, though this was more than 3.5 billion years ago.
The samples were collected last year, but researchers needed time for analysis. Perseverance has been roaming around the Martian surface since 2021. The six-wheeled rover has been collecting rock samples and regolith, using its onboard instruments for this analysis. This is also just the beginning of the research required here.
“Ultimately, follow-on research will provide us with a suite of testable hypotheses for how to determine whether biology is responsible for the generation of these features,” Hurowitz added.
