This is a photo of the surface of Saturn's moon Enceladus, taken by the Cassini space probe. It's part of the evidence researchers have collected which suggests that Enceladus is home to not only a subterranean ocean, but also a surface covered in fine, ski-ready snow. More than 250 feet of the stuff, in fact. Perhaps even more awesome: Scientists think the snow doesn't fall from the sky on Enceladus. It sprays up out of the ground. From National Geographic:
The researchers think superfine snowflakes are blasted out of geyser-like jets, which emanate from long fissures called tiger stripes on the moon's southern hemisphere. Some of the snow from these plumes falls back to the moon's surface, coating older fractures and craters in a slow process of accumulation.
Earthly geysers, such as Castle Geyser in Yellowstone National Park, emit steam and scalding water. Enceladus is so far from the sun, however, that its surface temperature is about -330°F (-200°C), causing water vapor spewed from its geysers to condense into ice crystals.
There are more images on Nat Geo, including an amazing shot by Cassini, showing how some of the crystals the geysers spew out actually leave the surface of the moon and become part of a ring around it.
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