Mars Kept a Secret for 3.5 Billion Years – NASA’s Curiosity Rover Finally Dug It Up

Scientists using NASA’s Curiosity rover have discovered siderite—an iron carbonate—in the sulfate-rich rocks of Gale Crater, solving a long-standing mystery about Mars’ missing carbonates. This find provides powerful new clues about the planet’s ancient atmosphere and supports theories that it once harbored conditions suitable for liquid water. The discovery challenges previous satellite data and suggests [...]