Comet mission loses some focus

On July 4, the Deep Impact spacecraft is scheduled to fire a 1,800-kilogram projectile into the icy heart of comet Tempel-1. The craft remains on course for that encounter, but its main camera won’t record the landmark event quite as sharply as astronomers had expected. Tests have revealed that the camera has only one-third to one-fourth the resolution it was designed to have, NASA announced March 25.