NASA’s Perseverance rover found potential biosignatures in a Jezero Crater rock nicknamed “Sapphire Canyon,” collected from a site called Cheyava Falls. The 3.5-billion-year-old sample is rich in organic carbon, sulfur, oxidized iron, and phosphorus—elements that could support microbial life. NASA calls it the closest sign of ancient life yet, but stresses more study and sample return are needed.