NASA's Mars rover discovers potential biosignature

LOS ANGELES, Sept. 10 (Xinhua) -- A sample collected by NASA's Perseverance Mars rover from an ancient dry riverbed in Jezero Crater may contain evidence of ancient microbial life, the agency said on Wednesday.

The sample, called "Sapphire Canyon," was taken last year from a rock named "Cheyava Falls" and contains potential biosignatures, according to a study published Wednesday on the journal Nature.

A potential biosignature is a substance or structure that might have a biological origin but requires more data or further study before a conclusion can be reached about the absence or presence of life, according to NASA.

Perseverance encountered the Cheyava Falls site in July 2024 while exploring the "Bright Angel" formation, a group of rocky outcrops located along the northern and southern edges of Neretva Vallis. This ancient river valley, about 400 meters wide, was carved long ago by water rushing into Jezero Crater.

"This finding by Perseverance ... 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," said acting NASA Administrator Sean Duffy.

The rover's science instruments found that the formation's sedimentary rocks are composed of clay and silt, which, on Earth, are excellent preservers of past microbial life. They are also rich in organic carbon, sulfur, oxidized iron (rust) and phosphorous.

"The combination of chemical compounds we found in the Bright Angel formation could have been a rich source of energy for microbial metabolisms," said Perseverance scientist Joel Hurowitz of Stony Brook University in New York and the study's lead author. "But just because we saw all these compelling chemical signatures in the data didn't mean we had a potential biosignature. We needed to analyze what that data could mean."

"Sapphire Canyon" is one of 27 rock cores the rover has collected since landing at Jezero Crater in February 2021. ■