NASA’s Curiosity rover finds major clue that Mars was once habitable NASA's Curiosity rover has found iron-rich carbonates on Mars — a major clue that the Red Planet used to be habitable. Astrobitica April 21, 2025 (Last updated: April 21, 2025) 1 minute read NASA’s Curiosity rover has found iron-rich carbonates on Mars — a major clue that the Red Planet used to be habitable. About the Author Astrobitica Administrator Visit Website View All Posts Post navigation Previous: SpaceX launches cargo Dragon to ISS with additional crew suppliesNext: Astronomers determine the fate of a compact dwarf galaxy