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It's Official! Water Ice Discovered on Mercury

Shown in red are areas of Mercury’s north polar region that are in shadow in all images acquired by MESSENGER to date. Image coverage, and mapping of shadows, is incomplete near the pole. The polar deposits imaged by Earth-based radar are in ye

NASA spacecraft maps planet Mercury

The closest planet to the sun hasn't received as much scientific attention as some of its more flashy solar system neighbors, such as Mars, but NASA's Messenger spacecraft is helping to close the gap. The probe has been in orbit around Mercury since March 2011, and its team announced Feb. 28 that the spacecraft had finished mapping the planet's surface.