Scientists marvel at comet collision

Deep Impact’s fireworks continue longer than expected

A space probe's direct hit on a comet millions of miles from Earth drew oohs and ahs on Monday from astronomers, who said the celestial fireworks show could continue for weeks.

Hours after the Deep Impact mission’s refrigerator-sized Impactor probe collided with Comet Tempel 1, the Flyby mothership still spotted plumes of gas and dust flying out from the impact crater.

"If there are lots of volatiles there, the outgassing will continue to go on for some time ... [perhaps] a matter of weeks," principal scientific investigator Michael A'Hearn said Monday during a post-impact briefing at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
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