C&EN: LATEST NEWS - Preparing For Impact

From the Chemical & Engineering News:

After six months of space flight, an 800-lb spacecraft carrying 317 lb of copper is preparing to slam into the comet Tempel-1 on July 4. The resulting impact crater—expected to kick up material from the comet’s still-mysterious nucleus—could be as small as a house, or as big as a football stadium.

Scientists hope that this unprecedented access to a comet’s innards will help them understand the solar system’s formation. Right now, all they know is that Tempel-1’s nucleus, which is about the size of Washington, D.C., is “a jet-black, pickle-shaped, icy dirt ball,” Donald K. Yeomans, coinvestigator for the Deep Impact mission at NASA’s Jet Propulsion Laboratory (JPL), said at a press briefing at National Aeronautics & Space Administration headquarters in Washington, D.C.

Space-based telescopes such as NASA’s Hubble, Chandra, and Spitzer and the European Space Agency’s Rosetta spacecraft, also en route to a comet, will track the event. One hundred or so professional ground-based telescopes and a small army of amateur astronomers will also be watching the show, hoping to spot signs of the impact blast...

Full article by Elizabeth K. Wilson