In July, 2024, after covering 18 miles in nearly three and a half years, it arrived at a quarter-mile-wide river valley that is home to a 3.2-ft.-long rock NASA scientists have dubbed Cheyava Falls—and there it hit paydirt. As a new paper in Nature reports, a sample Perseverance drilled from the rock may contain potential biosignatures of long ago microbial life.

“This finding by Perseverance…is the closest we have ever come to discovering life on Mars,” said acting NASA administrator Sean Duffy in a statement. “The identification of a potential biosignature on the Red Planet is a groundbreaking discovery, and one that will advance our understanding of Mars.”

What it found was a rock streaked in a range of colors—red, green, purple, and blue—flecked with poppy-seed-like dots and decorated with what the Perseverance scientists compared to dull yellow leopard spots. That said a lot. As the rover’s instruments confirmed, the red is iron-rich mud, the purple is iron and phosphorous, the yellow and green are iron and sulfur. All of those elements serve as something of a chow line for hungry microbes.

The poppy seeds and leopard spots, meantime, resemble markings left behind by metabolizing microbes on Earth.