Mars mineral map shows widespread ancient water evidence

Researchers at Australia's Edith Cowan University re‑examined hundreds of measurements taken by NASA's Spirit rover in the Gusev crater between 2004 and 2010. Using modern analytical techniques they combined data from 32 sites to produce the most detailed map to date of iron‑bearing minerals in the Martian regolith. The study identified crystalline hematite and altered magnetite, minerals that form when rocks interact with liquid water, indicating that water was once more extensive on Mars than previously thought. Earlier analyses had missed hematite because its concentrations were low and obscured by instrument noise. The findings support earlier rover observations—Curiosity’s detection of ancient lakes in Gale crater and Perseverance’s search for dried river deltas—suggesting that water may have covered large portions of the planet's surface in the past.