Deep Impact
• Launch date: 7 January 2005
• Orbital insertion: 4 July 2005
• End of mission: 3 August 2005
• Agency: NASA
Famous for its July 4, 2005 planned impact with comet Tempel 1 that generated a brilliant flash of light later discovered to be ice and dust debris ejecting from the fresh impact crater, the Deep Impact mission was the first attempt to peer beneath the surface of a comet.
Deep Impact, which released an impactor on comet Tempel 1 to expose materials on its surface, revealed a number of new findings about comets and their composition, including evidence of water ice and organic materials. Researchers now believe that comets may have transported these compounds to Earth at one time, playing an essential role in the formation of the solar system and life on Earth.