Life on Mars? NASA’s Perseverance rover finds signs of ancient microbes
A year after NASA’s Perseverance rover drilled into a rock called Cheyava Falls, scientists have revealed that the sample it collected, known as Sapphire Canyon, contains what could be a chemical fingerprint of ancient microbial life.
Published this week in the journal Nature, the finding has been described by NASA as the closest humanity has come to evidence of life beyond Earth.
Ancient river valley on Mars may have preserved signs of life
Perseverance came across the Cheyava Falls outcrop in July 2024 while exploring the Bright Angel formation, a network of rocky deposits on the edges of Neretva Vallis. Billions of years ago, this broad river valley funnelled water into Jezero Crater, once home to a vast lake.
Sedimentary rocks in the area are rich in clay, silt and organic carbon, materials that on Earth are excellent preservers of microbial remains. These rocks also contain sulphur, oxidised iron and phosphorus—potential fuel sources for primitive life.
Scientists had long suspected Jezero Crater to be one of the most promising sites for astrobiology, but the rover’s latest findings suggest the Red Planet may have been habitable for longer, and later, than many expected.
Perseverance rover finds strange spots in Martian mudstone
When Perseverance trained its suite of instruments on Cheyava Falls, particularly PIXL and SHERLOC, it detected colourful spots patterned across the rock surface. High-resolution images revealed what researchers called “leopard spots”: mineral reaction fronts rich in two iron-based minerals, vivianite and greigite.
On Earth, vivianite often appears in sediments around decaying organic matter, while greigite can be formed by certain microbes. Together, the minerals are potential traces of electron-transfer reactions—the same kind microbes use to generate energy.
Yet as scientists stress, the minerals could also form through geological processes without biology. High heat, acidic conditions or purely chemical reactions could have created them, although there is no evidence of such extreme conditions in the Bright Angel rocks.
Why Perseverance’s discovery could reshape the search for life on Mars
The Cheyava Falls mudstones are among the youngest sedimentary rocks Perseverance has studied. Until now, researchers assumed that only much older rocks would contain traces of life. The new data suggests Mars may have supported habitable conditions more recently in its history than previously believed.
“This is a potential fingerprint of microbial life,” said Joel Hurowitz, lead author of the Nature paper. “But just because the chemistry looks compelling doesn’t mean it’s proof of biology. That’s why further study is essential.”
Katie Stack Morgan, Perseverance’s project scientist, cautioned: “Astrobiological claims require extraordinary evidence. This is a crucial step forward, but we cannot yet rule out non-biological explanations.”
Mars Sample Return mission holds the answers
Perseverance has already collected 27 rock cores since landing in Jezero Crater in 2021, sealing them in slim metal tubes for possible return to Earth.
NASA designed the rover’s instruments to identify potential biosignatures but always planned for Earth-based laboratories to conduct the decisive tests.
“We’ve basically thrown the entire rover payload at this rock,” said Stack Morgan. “We’re now at the limits of what Perseverance can do on the surface. The next chapter depends on bringing these samples home.”
That plan—the Mars Sample Return (MSR) mission—has faced years of delays and spiralling costs. Initially budgeted at around $3 billion with a target return date of 2033, estimates now range between $6–$11 billion, pushing possible delivery of the samples back to the mid-2030s. Even so, NASA remains committed, with officials considering alternative mission designs to cut costs and speed up delivery.
Are we alone? NASA weighs possible signs of life on Mars
For scientists, the “leopard spots” in Martian mudstone are not just about mineralogy—they speak to humanity’s oldest question: whether life exists beyond our planet.
Acting NASA Administrator Sean Duffy described the finding as a milestone: “This is the closest we have ever come to discovering life on Mars. The identification of a potential biosignature on the Red Planet is a groundbreaking discovery.”
Nicky Fox, NASA’s associate administrator for science, added: “Today we are one step closer to answering one of humanity’s most profound questions: are we truly alone in the universe?”
Yet excitement remains tempered by scientific caution. The leopard spots may be Mars’s most compelling whisper of life yet, but only laboratory instruments on Earth can tell whether those whispers are biological in origin or echoes of pure geology.
What comes next for Perseverance and its search for life on Mars
As Perseverance continues its trek across Jezero Crater, every core sample it seals brings scientists closer to resolving the mystery. The rover is not only seeking traces of life but also providing environmental data for future human explorers.
If the rocks of Sapphire Canyon do prove to hold ancient biosignatures, they would mark humanity’s first confirmed evidence of life beyond Earth—a discovery that would redefine our place in the cosmos.
Until then, the samples lie waiting in their metal tubes, silent messengers from another world, holding secrets that could change everything we know.
