In addition to the Rosetta spacecraft, NASA is planning an intercept mission named Deep Impact to impact comet Tempel 1 to record and analyze the impact. This impact is expected to reveal significant insights regarding the composition of the comet’s core.
On December 30, 2004, NASA will, assuming weather and technology permit, launch a flyby spacecraft and an impactor to intercept and impact the comet. The two crafts are expected to reach rendezvous with the comet on July 4, 2005.
On that date, the impactor will collide with the comet and the flyby craft will record the results, which will be transmitted back to NASA via X-band communications through their Deep Space Network of listening stations.
NASA plans to broadcast the event on television and over the internet.
Information on the project can be found here:
http://deepimpact.jpl.nasa.gov/faq.html
Information on observing the impact can be found here:
http://deepimpact.jpl.nasa.gov/science/observations.html
This entry also posted in the American Military University Introduction to Astronomy newsgroup.