What’s the main task for "Deep Impact" this time?

Eighty-three million miles out in space, a comet had a visitor from planet Earth earlier today. The comet is named Tempel 1 and the visitor was called Deep Impact, which also describes its mission to slam into the speeding comet and learn just what it’s made of. Well, it worked. It was a brilliant success. The picture perfects collision of Deep Impact’s unmanned probe, the explosion of images and data. Even Mission Controllers could barely believe they’d pulled off such a brash technological feat.