CAPE CANAVERAL, FL – NASA’s Perseverance Mars rover has discovered rock samples that contain ‘potential biosignatures’ amounting to the best ever evidence to date for microbial life existing on the Red Planet in the distant past billions of years ago – agency officials announced at a news briefing and in a new press release on Sept. 10.
However the discovery at Jezero Crater by Perseverance does not amount to direct evidence for actually finding past life – scientists and NASA are careful to point out.
The only way to know for sure is to bring the rock and soil samples back to Earth for high powered scientific analysis
Perseverance found what appeared to be colorful spots nicknamed ‘leopard spots’ while exploring the “Bright Angel” formation- that could have been left behind by microbial life under the right conditions
“The combination of chemical compounds we found in the Bright Angel formation could have been a rich source of energy for microbial metabolisms,” said Perseverance scientist Joel Hurowitz of Stony Brook University, New York and lead author of the paper.
“But just because we saw all these compelling chemical signatures in the data didn’t mean we had a potential biosignature. We needed to analyze what that data could mean.”
NASA had a planned mission called ‘Mars Sample Return’ or MSR jointly along with ESA but the costs ballooned to about $10 Billion – and the Trump Administration has basically cancelled that plan and placed the project on indefinite hold.
NASA is searching for an alternative architecture to return the dozens of core samples collected thus far by Perseverance since its touchdown on Mars in 2021
The rock sample was collected last year by NASA’s Perseverance Mars rover from an ancient dry riverbed in Jezero Crater – as initially announced a year ago.
Now, after a year of further study the agency confirms it could preserve evidence of ancient microbial life.
The sample “Sapphire Canyon” was collected from a rock named “Cheyava Falls” last year and contains potential biosignatures, according to a new paper published in the journal Nature on Sept. 10.
A potential biosignature is a substance or structure that might have a biological origin but requires more data or further study before a conclusion can be reached about the absence or presence of life.
Perseverance came upon Cheyava Falls in July 2024 while exploring the “Bright Angel” formation, a set of rocky outcrops on the northern and southern edges of Neretva Vallis, an ancient river valley measuring a quarter-mile (400 meters) wide that was carved by water rushing into Jezero Crater long ago.
First to collect data on this rock were Perseverance’s PIXL (Planetary Instrument for X-ray Lithochemistry) and SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) instruments. While investigating Cheyava Falls, an arrowhead-shaped rock measuring 3.2 feet by 2 feet (1 meter by 0.6 meters), they found what appeared to be colorful spots. The spots on the rock could have been left behind by microbial life if it had used the raw ingredients, the organic carbon, sulfur, and phosphorus, in the rock as an energy source.
In higher-resolution images, the instruments found a distinct pattern of minerals arranged into reaction fronts (points of contact where chemical and physical reactions occur) the team called leopard spots. The spots carried the signature of two iron-rich minerals: vivianite (hydrated iron phosphate) and greigite (iron sulfide). Vivianite is frequently found on Earth in sediments, peat bogs, and around decaying organic matter. Similarly, certain forms of microbial life on Earth can produce greigite.
NASA Biosignatures Media Briefing held 10 Sept 2025
Caption: Streamed live on Sep 10, 2025. Experts discuss the analysis of a rock sampled by NASA’s Perseverance Mars rover last year. The sample, called “Sapphire Canyon,” was collected in July 2024 from a set of rocky outcrops on the edges of Neretva Vallis, a river valley carved by water rushing into Jezero Crater long ago. Participants in the news conference include:
• Acting NASA Administrator Sean Duffy
• NASA Associate Administrator Amit Kshatriya
• Nicky Fox, associate administrator, Science Mission Directorate, NASA Headquarters
• Lindsay Hays, senior scientist for Mars Exploration, Planetary Science Division, NASA Headquarters
• Katie Stack Morgan, Perseverance project scientist, NASA’s Jet Propulsion Laboratory
• Joel Hurowitz, planetary scientist, Stony Brook University, New York
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