spacetoday.net: Water ice spotted on surface of comet

Posted: Mon, Feb 6, 2006, 6:24 AM ET (1124 GMT)
Tempel 1 comet after Deep Impact collision (NASA/JPL)

Planetary scientists said last week that they have detected water ice on the surface of comet Tempel-1, the first detection of ice on the surface of any comet. In a paper published in the latest issue of the journal Science, researchers involved with NASA's Deep Impact mission said they were able to detect water ice in three small areas on the surface of the comet's nucleus prior to the collision of the spacecraft's impactor probe with the nucleus last July. While scientists had known for some time that comets contained water ice, it had not been directly detected on a nucleus before now. The fact that ice was seen in only a few small areas suggests that most cometary water ice is located below the surface.