Summary: July 4th is Independence Day In the United States, and Americans typically enjoy their holiday with a few fireworks. But up in space, 133 million kilometres away, there's going to be an even more spectacular show... Deep Impact. On July 4th, a washing machine-sized spacecraft is going to smash into Comet Tempel 1, carve out a crater, and eject tonnes of ice and rock into space. The flyby spacecraft will watch the collision from a safe distance, and send us the most spectacular pictures ever taken of a comet - and its fresh bruise. Dr. Lucy McFadden is on the science team for Deep Impact, and speaks to me from the University of Maryland.
