In July 2024, the rover Perseverance collected a sample of mudstone that contained the most compelling evidence of past Martian life discovered so far. Launched in 2020, Perseverance’s mission was to collect rock samples and search for signs of ancient life. Now, it has achieved that goal.
The sample, named Sapphire Cannon, was taken from Cheyava Falls—a dried-up riverbed in Jezero Crater. Sapphire Cannon contained the minerals gregite and vivianite. These minerals could have formed through chemical reactions involving microbes.
Gregite is a hydrated iron phosphate often excreted by soil-dwelling microbes on Earth. Vivianite, an iron sulfide, is found in decaying matter here as well. The discovery of these minerals provides compelling evidence that microbial life might once have existed on Mars.
NASA also determined that Cheyava Falls is rich in organic carbon, phosphorus, and oxidized iron—chemical compounds that could have supported life.
Sean Duffy, interim administrator of NASA, told The New Yorker that this is “the clearest sign of life that we’ve ever found on Mars.” He added that, after a year of review, NASA scientists have not found another explanation for how these minerals formed.
Still, the evidence doesn’t definitively prove that alien life once existed on the red planet. Both gregite and vivianite can also form abiotically, meaning without any living organisms. They could have formed at extremely high temperatures or in acidic conditions. However, given the state of Sapphire Cannon, this seems unlikely, as the sample doesn’t appear to have been exposed to such extremes.
The search for life on Mars may soon face new obstacles. President Trump’s proposed budget cuts could reduce NASA’s funding to a quarter of its current level. This would cancel the mission to bring Sapphire Cannon back to Earth for further analysis, and disable Maven and Mars Odyssey, which Perseverance uses to communicate. The cuts would also cancel 41 science missions and reduce Perseverance’s funding by 23%. These changes will take effect on October 1 unless Congress passes an appropriations bill to provide necessary funding.
In conclusion, while this discovery is a major step toward finding a biosignature on Mars and searching for alien life, conclusive evidence may still be far off. For all you science fiction fans, though, we might be closer than ever to discovering extraterrestrial life.
