WASHINGTON: A sample obtained by Nasa’s Perseverance rover of rock formed billions of years ago from sediment on the bottom of a lake contains potential signs of ancient microbial life on Mars, according to scientists, though the minerals spotted in the sample also can form through nonbiological processes.

The discovery, detailed in research published on Wednesday, represents one of the best pieces of evidence to date about the possibility that Earth’s planetary neighbour once harboured life.

Since landing on the Martian surface in 2021, the six-wheeled rover has been exploring Jezero Crater, an area in the planet’s northern hemisphere that once was flooded with water and home to an ancient lake basin, as it seeks signs of ancient life.

Perseverance has been collecting samples of rock and loose material called regolith and analysing them with its various onboard instruments.

The rover obtained the newly described sample, called the Sapphire Canyon sample, in a place called the Bright Angel rock formation.

This formation consists of fine-grained mudstones and coarse-grained conglomerates, a kind of sedimentary rock composed of gravel-sized particles cemented together by finer-grained sediments.

Stony Brook University planetary scientist Joel Hurowitz, who led the study published in the journal Nature, said that a “potential biosignature” was det­ected in multi-billion-year-old sedimentary rocks.

Published in Dawn, September 11th, 2025