Deep Impact will deploy a probe that will be "run over" by the nucleus of comet Tempel 1.
A pre-launch briefing on the comet hunting mission will be held at 1 p.m. EST, Tuesday, Dec. 14 at NASA Headquarters.
NASA's Deep Impact spacecraft has arrived in Florida to begin final preparations for a launch on Dec. 30, 2004.
People worldwide may celebrate July 4, 2005, as the day their names reach a comet.