NASA’s Perseverance rover has discovered a rock on Mars that may hold fossil evidence of ancient microbial life. The arrowhead-shaped, vein-filled rock, nicknamed “Cheyava Falls,” was found in the northern part of Neretva Vallis, an ancient river valley on Mars, on July 21, 2024. Scientists believe this rock could contain some of the earliest signs of microbial life that existed billions of years ago when the area possibly had flowing water.
Instruments aboard Perseverance analyzed the rock’s chemical makeup and structure, finding qualities that match those expected from ancient microbial fossils. The rock contains large veins of calcium sulfate and reddish-brown bands, indicating the presence of hematite (a mineral linked to Mars’ rusty surface).
Closer inspection revealed dozens of irregularly shaped, off-white spots surrounded by black rings, resembling patterns sometimes seen in fossilized microbial life on Earth. Perseverance’s PIXL (Planetary Instrument for X-ray Lithochemistry) found that the black halos contain iron and phosphate, elements often connected to microbial fossils.
Ken Farley, Perseverance project scientist at Caltech, described Cheyava Falls as “the most puzzling, complex, and potentially important rock yet investigated by Perseverance.” David Flannery, an astrobiologist on the mission team, noted that these features are commonly linked to ancient microbial life found beneath Earth’s surface.
This discovery could represent a major step toward finding evidence of life beyond Earth. However, confirming this will require more detailed study of samples returned to Earth in future missions. Until then, Cheyava Falls remains one of the most promising clues in the search for past life on Mars.