Deep Impact (spacecraft)
 Deep Impact was a NASA space probe launched on January 12 2005. It was designed to study the interior composition of the comet 9P/Tempel by releasing an impactor into the comet. At 5:52 UTC on July 4 2005 the impactor successfully collided with the comet's nucleus. The impact excavated debris from the interior of the nucleus allowing photographs of the impact crater. The photographs showed the comet to be more dusty and less icy than had been expected.