Dawn Spacecraft Finds Traces of Water on Vesta

Vesta, the second most massive asteroid in the Solar System, after the dwarf planet Ceres, was thought to be a dry place, but the most recent evidence from NASA’s spacecraft Dawn has found that smaller, water-rich asteroids once implanted themselves in Vesta’s surface. The water is locked up in hydrated minerals until subsequent impacts create enough heat to melt the rock and release the water as gas

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