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 yellow (from Image 2.1), and the background image is the mosaic of MESSENGER images from Image 2.2. This comparison indicates that all of the polar deposits imaged by Earth-based radar are located in areas of persistent shadow as documented by MESSENGER images. Image released Nov. 28, 2012.
It's time to add Mercury to the list of worlds where you can go ice-skating. Confirming decades of suspicion, a NASA spacecraft has spotted vast deposits of water ice on the planet closest to the sun.
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