We could be one step closer to proving alien existence.<\/p>\n
In 1996, a group of NASA scientists made a stunning announcement: The discovery of what appeared to be bacterial fossils on Mars. President Bill Clinton discussed the discovery on camera and people celebrated the apparent answer to the age-old question of whether we\u2019re alone in the universe.<\/p>\n
Within a few years, further scientific scrutiny revealed the so-called fossils could all be explained by abiotic (non-life) processes<\/a>. Nearly 30 years later we\u2019re still not sure if life ever existed on Mars\u2014but that might be poised to change. NASA\u2019s Perseverance Mars rover may have already sampled some Martian fossils, according to a September 10, 2025 study published in the journal Nature<\/a>.<\/p>\n Exciting as it might be, extraordinary claims require extraordinary evidence and it doesn\u2019t get much more extraordinary than aliens.<\/p>\n Cheyava Falls, the Mars rock with signs of alien life<\/p>\n In fairness to the Perseverance rover, this is exactly what it was built for. Nicknamed Percy, the machine was sent to Jezero crater, the remains of an ancient riverbed. If life ever existed on Mars, Jezero is the sort of place we might expect to find it.<\/p>\n RELATED: Everything to Know About the Mars 2020 Perseverance Rover Mission: What it’s Done, What’s Next<\/a><\/p>\n Since Perseverance landed on February 18, 2021, it\u2019s been collecting samples of geologically interesting rocks, including one nicknamed Cheyava Falls. It\u2019s an arrowhead-shaped rock about three feet long and two feet wide. White streaks on its surface suggest water flowed through it in the past but researchers were most interested in \u201cleopard spots,\u201d surface patterns which, on Earth, are typically signatures of microbial activity.<\/p>\n Perseverance found Cheyava Falls in July 2024 while exploring an area known as the Bright Angel formation. The rover is equipped with tools for gathering samples, but also for examining them, like PIXL (Planetary Instrument for X-ray Lithochemistry) and SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals). Early analysis of Cheyava Falls determined it was sedimentary rock made of clay and silt, rich in organic carbon, sulfur, phosphorus, and oxidized iron. It\u2019s the kind of rock Earth microbes would like.<\/p>\n High resolution photos later revealed patterns in the mineral deposits containing vivianite and greigite, two iron-rich minerals. On Earth, vivianite is found in peat bogs and around decaying matter and greigite is produced by microbes.<\/p>\n \u201cThe combination of chemical compounds we found in the Bright Angel formation could have been a rich source of energy for microbial metabolisms,\u201d said Perseverance scientist and lead author Joel Hurowitz in a statement<\/a>. \u201cBut just because we saw all these compelling chemical signatures in the data didn\u2019t mean we had a potential biosignature. We needed to analyze what that data could mean.\u201d<\/p>\n Put simply, a biosignature is not direct evidence of life. We\u2019re not looking at Martian microbes, we\u2019re looking at artifacts which could have been left behind by Martian microbes. It\u2019s like finding a big pile of abandoned branches blocking up a river in the woods. We have to be sure those trees weren\u2019t knocked down by a landslide before we start blaming beavers.<\/p>\n RELATED: So, Astronomers *May* Have Found Evidence of Life on Venus<\/a><\/p>\n In the case of leopard spots on rocks, they can be formed by non-biological processes like sustained high temperatures or high acidity. However, scientists found no evidence of either condition in the nearby rocks. Without more evidence, what scientists can confidently say right now is that the characteristics of Cheyava Falls are consistent with past microbial life, and there\u2019s no known alternative explanation that fits the available evidence.<\/p>\n \u201cThis paper takes the next step,\u201d explained The Planetary Society\u2019s Bruce Betts<\/a>. (Betts was not involved with the Nature study.) \u201cBut further study by other scientists will be required before we can see if this rock provides an answer to the profound question of whether there was once life on another world.\u201d<\/p>\n A Mars Sample Return mission could confirm ancient life on Mars<\/p>\n \u201cThis finding by Perseverance, launched under President Trump in his first term, 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, and one that will advance our understanding of Mars,\u201d said acting NASA Administrator Sean Duffy. \u201cNASA\u2019s commitment to conducting Gold Standard Science will continue as we pursue our goal of putting American boots on Mars\u2019 rocky soil.\u201d<\/p>\n It\u2019s worth noting that while Perseverance was launched July 30, 2020 during Trump\u2019s first term, the project predates his administration. NASA first announced a 2020 Mars rover in 2012<\/a>. Additionally, budget cuts proposed by the current Trump administration<\/a> would stall or kill existing and planned missions, including efforts to reach the red planet.<\/p>\n Perseverance is a robot carrying a limited chemistry set, there\u2019s only so much it can do. To really get to the bottom of Cheyava Falls and the other rocks Percy has sampled, we\u2019re going to need to bring them home. In fact, that was always the plan. Perseverance is collecting samples of rocks throughout its travels and preparing them for eventual pickup. A joint mission between NASA and ESA (the European Space Agency) is supposed to go to Mars, pick up the sample containers, and bring them back. But that\u2019s only if the mission happens, something which appears increasingly unlikely.<\/p>\n The Mars Sample Return mission is one of many planned projects threatened by proposed budget cuts. Plans to decimate NASA\u2019s budget will cancel at least 41 missions<\/a> (some of which are already paid for, launched, and in progress). Mars Sample Return is among the missions on the chopping block.<\/p>\n