Our Daily Bread

Orbiting our planet at speeds more than 4.5 miles per second is a growing collection of space junk. Nuts, bolts, and other discarded debris from space flights are presenting a real hazard to future spacecraft. Their sheer speed makes the tiniest object strike with the impact of a bullet. During one of the shuttle missions, a speck of paint created a pit a quarter-inch wide in a window of the craft.