NASA’s Curiosity rover has discovered siderite, a carbonate mineral, beneath Mars’ surface—providing new clues that the Red Planet may have once had conditions suitable for life billions of years ago.

A mineral called siderite found abundantly in rock drilled by a NASA rover on the surface of Mars is providing fresh evidence of the planet's warmer and wetter ancient past when it boasted substantial bodies of water and potentially harbored life.

NASA believes that examining other sulfate-rich areas could validate these findings and further illuminate Mars’ transformation as its atmosphere dissipated.