For as long as humanity has gazed into the night sky, Mars has shimmered in our imagination as a world of possibility. Its rusty deserts, canyons deeper than Earth’s Grand Canyon, and dried-up riverbeds have long whispered of a wetter, more vibrant past. But the latest findings from NASA’s Perseverance rover, in collaboration with researchers at Imperial College London, bring that whisper closer to a shout.
A new study, published in Nature in September 2025, suggests Mars was once not only habitable but also may have hosted microbial processes. For the first time, scientists have identified minerals and organic matter in Martian rocks that look strikingly similar to features shaped by life on Earth. The work does not prove life once thrived on Mars—but it opens one of the most tantalizing chapters yet in humanity’s search for our cosmic neighbors.
The Bright Angel Mystery
The focus of the discovery is a pale-toned rocky outcrop in Jezero Crater, an ancient impact basin that once held a vast lake. Perseverance has been exploring the crater since 2021 as part of NASA’s Mars 2020 mission, chosen because river deltas and lakebeds are prime candidates for preserving traces of past life.
As the rover drove through Neretva Vallis—an ancient river valley leading into the crater—it stumbled upon something surprising. Instead of the coarse sands and gravels you’d expect from a riverbed, Perseverance’s instruments revealed fine-grained mudstones and clays. These minerals usually form in calm waters like lakes, not rushing streams.
The rocks belonged to what scientists dubbed the Bright Angel formation, and their presence suggested a remarkable scenario: sometime in Mars’ distant past, the valley itself was flooded and transformed into a lake.
“This is unusual but very intriguing, as we wouldn’t expect to find such deposits in Neretva Vallis,” said Alex Jones, a Ph.D. researcher at Imperial College London who worked on the study. “Our analysis indicates a past, low-energy lake environment—and that is precisely the kind of habitable environment we have been looking for.”
Signs Written in Stone
Finding a lake is exciting enough, but what scientists saw inside the rocks was even more extraordinary. Perseverance, equipped with cutting-edge instruments such as PIXL (Planetary Instrument for X-ray Lithochemistry) and SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals), revealed tiny nodules and chemical “reaction fronts” within the mudstones.
These millimeter-sized features turned out to be enriched in minerals such as iron-phosphate and iron-sulfide, likely vivianite and greigite. On Earth, these minerals often form as by-products of microbial metabolism—processes where microbes harvest energy by transferring electrons in redox (reduction-oxidation) reactions.
In other words, the rocks show chemical fingerprints that could have been shaped by microbes billions of years ago.
Professor Sanjeev Gupta of Imperial College, a senior author on the study, was both thrilled and cautious:
“This is a very exciting discovery of a potential biosignature, but it does not mean we have discovered life on Mars. We now need to analyze this rock sample on Earth to truly confirm if biological processes were involved or not.”
Why This Matters
The idea that Mars once had lakes, rivers, and even oceans is not new. But evidence for habitable environments is only half the story—what scientists crave are biosignatures: chemical or structural traces that point to life itself.
The Bright Angel rocks contain organic carbon and minerals shaped by redox reactions. On Earth, such pairings often indicate microbial ecosystems at work. While it’s still possible that these features were created through abiotic (non-living) chemistry, their resemblance to terrestrial biosignatures makes them compelling.
Matthew Cook, Head of Space Exploration at the UK Space Agency, emphasized the importance of the discovery:
“These findings represent the most promising evidence yet discovered. While we must remain cautious, the chemical signatures in these Martian rocks could reflect biological processes that we see on Earth. They bring us closer to answering one of humanity’s greatest questions: are we alone in the universe?”
Waiting for Earth to Decide
The ultimate test lies not on Mars, but back on Earth. Perseverance has already drilled and cached a core sample from Bright Angel, nicknamed “Sapphire Canyon.” This sample, along with others collected across Jezero, is awaiting return as part of the Mars Sample Return mission—a collaboration between NASA and the European Space Agency.
If all goes to plan, those samples could arrive on Earth in the 2030s. Once here, they will be examined with state-of-the-art instruments far more sensitive than those Perseverance carries. Scientists will probe their atomic structures, analyze isotopes, and look for complex organic molecules that cannot be explained by simple chemistry. Only then will we know whether Bright Angel’s secrets truly tell a story of life.
“This discovery is a huge step forward—the samples we helped characterize are among the most convincing we have,” said Professor Gupta. “It highlights the power of collaboration and advanced robotics in planetary exploration.”
A Window Into Mars’ Forgotten Era
Beyond the possibility of life, the Bright Angel findings shed light on a crucial period in Martian history. Billions of years ago, Mars was warmer, wetter, and wrapped in a thicker atmosphere. Lakes like the one in Jezero would have dotted its surface, providing stable environments where life might have taken root.
But over time, Mars lost its atmosphere and most of its water, becoming the frozen desert we see today. The minerals and organics preserved in Bright Angel are like time capsules, preserving a snapshot of conditions when Mars was more Earth-like—and perhaps alive.
The Emotional Pull of Discovery
The science is rigorous, but the implications reach deep into the human spirit. If these rocks do indeed carry the whispers of ancient microbes, it would mean life is not unique to Earth. It would mean the universe is fertile, that biology blooms wherever conditions allow, and that we are part of a vast cosmic family.
Even if the features turn out to be abiotic, the discovery still tells us something profound: Mars had all the ingredients necessary for life. And that fact alone reshapes our understanding of what kind of universe we live in—a universe where habitable worlds might be common, and where Earth may not be the only cradle of life.
Looking Ahead
The next decade will be decisive. The Mars Sample Return mission, along with Europe’s upcoming Rosalind Franklin rover, will dig deeper into the Red Planet’s secrets. Each step brings us closer to answering a question that has haunted humanity for millennia: are we alone?
For now, the Bright Angel formation stands as one of the most promising leads in the search for life beyond Earth. Its mudstones, nodules, and hidden organics remind us that the universe holds mysteries not yet fully told.
Perhaps, tucked inside a Martian rock billions of years old, lies the first evidence that life once took hold on another world. And if so, Mars will no longer be just a planet we study from afar—it will be the second known home of life in the cosmos.
More information: Joel Hurowitz, Redox-driven mineral and organic associations in Jezero Crater, Mars, Nature (2025). DOI: 10.1038/s41586-025-09413-0. www.nature.com/articles/s41586-025-09413-0
Janice L. Bishop et al, Mystery Martian minerals hint at the planet’s complex geochemical past, Nature (2025). DOI: 10.1038/d41586-025-02597-5 , doi.org/10.1038/d41586-025-02597-5
