Scientists at the U.S. space agency say they have found a small hole in an exterior panel on the space shuttle , which completed a mission to the International Space Station last month.
NASA reported on its website that a piece of space debris likely made the hole in a radiator panel. But it said the blow did not endanger shuttle crew members. The hole, which NASA scientists informally called a "ding," measured about a quarter of a centimeter in diameter.
Damage to the shuttle 's exterior in 2003 was blamed for the destruction of the shuttle upon re-entry to the Earth's atmosphere. Engineers say a piece of hard foam broke off of the shuttle during takeoff and damaged the wing. All seven crew members died in the disaster.