Photo: Comet Hartley 2 Travels With a Posse of Snowballs

Discover how comet Hartley 2 creates its own snowstorm with ejected snowballs and frozen carbon dioxide. Explore NASA's latest pictures!

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Phil Plait has the report on NASA's latest pictures from the flyby of Hartley 2, which reveal that the comet is surrounded by a blizzard of snow and ice:

Wow! Most of those dots are not stars: they are actual snowballs, frozen matter that has been ejected by the comet itself! They range in size from a few centimeters to a few dozen across, so they really are about the size of snowballs you’d use in a snowball fight… or to make a snowman. But I wouldn’t recommend it: a lot of that material is not frozen water, it’s actually frozen carbon dioxide, or dry ice.

Find out what else we've learned about Hartley 2 and see more photos at Bad Astronomy

. Related Content: Bad Astronomy: Amazing Close-Ups of Comet Hartley 2!

80beats: Holy Hartley 2! What to Know About NASA’s Comet Flyby

80beats: Video: Comet Caught Crashing into the Sun

80beats: Spacecraft-Collected Comet Dust Reveals Surprises From the Solar System’s Boondocks

Bad Astronomy: Ten Things You Don’t Know About Comets

Image: NASA / JPL-Caltech / UMD

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