NASA’s Perseverance rover has found unusual “leopard spot” minerals in a Mars rock that may be signs of ancient microbial life, offering the strongest biosignature clue yet from Jezero Crater.
NASA’s Perseverance rover may have just stumbled on the most tantalizing evidence of Martian life to date. A rock sample nicknamed Sapphire Canyon—collected from Jezero Crater’s Bright Angel formation—contains strange mineral patterns that researchers say look eerily similar to biosignatures left behind by microbes on Earth.
The sample shows distinctive markings, dubbed “leopard spots,” made up of two unusual iron-rich minerals: vivianite and greigite. On Earth, both are frequently linked to environments shaped by microbial activity. Vivianite often appears in sediments and bogs, while greigite can form through processes driven by bacteria.
“This is the closest we’ve come to identifying a potential biosignature on Mars,” said Dr. Joel Hurowitz of Stony Brook University, lead author of the study published in Nature. “The chemical fingerprints we see strongly suggest energy sources that microbes could have exploited.”
The rover first encountered the rock, also called Cheyava Falls, in July 2024. Using its PIXL and SHERLOC instruments, Perseverance detected the colorful spots and mapped their chemical makeup. The patterns suggest electron-transfer reactions—processes microbes often rely on to fuel growth.
Still, scientists are treading carefully. Non-biological processes, such as heat or acidic conditions, can also produce the same minerals. But the Bright Angel formation shows no evidence of such extreme conditions, leaving biology as a compelling possibility.
Adding to the intrigue, the discovery was made in relatively young sedimentary rocks, challenging earlier assumptions that any traces of life would be locked only in Mars’s oldest terrains. This could mean the Red Planet remained habitable for longer—and perhaps later—than once believed.
NASA officials hailed the finding as a landmark moment. “Astrobiological claims require extraordinary evidence,” said Katie Stack Morgan, Perseverance’s deputy project scientist at JPL. “Getting this into peer review is a major step, but we cannot yet rule out non-biological explanations.”
The Sapphire Canyon sample is one of 27 rock cores Perseverance has collected since landing in February 2021. Eventually, scientists hope to bring these samples back to Earth for more definitive testing—a mission seen as crucial to answering humanity’s oldest question: Are we alone?
For now, those mysterious “leopard spots” keep Mars firmly in the running as a place where life may once have flickered.