Perseverance Rover Nears Marathon Milestone, Discovers Mars's Ancient Water History

Across the rust-colored plains of Mars, a rover built by human hands has quietly crossed the distance of a marathon — 42.195 kilometers — while doing something far more consequential than moving: reading the planet's oldest stones. NASA's Perseverance has found in the western frontier geological evidence that water once shaped the Martian mineral record, not as a passing event but as a formative force. These ancient rocks carry within them a diary of a world that may once have held the conditions for life, and the act of deciphering that diary is, in its way, humanity asking the oldest questio