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9.8.07

Snowball Fight in the Solar System

"One of the most surprising objects observed in X-rays are comets. X-rays are normally associated with the hottest things in the Universe, such as black holes. Comets, however, were described by Fred Whipple as being "dirty snowballs". So how does a snowball make X-rays? "

You can download this video here: Snowball Fight in the Solar System