Mr. Boehlert said a compilation of video clips that Admiral Gehman presented at his meeting showed that "the orbiter was shedding debris earlier than originally thought."

Discovery's external tank shed so much less debris than earlier ones that the shuttle had just 25 scars on its tiles, onesixth of the usual amount.

NASCAR parked Busch for pulling away and trying to drive back to the garage despite the fact that his car was shedding debris.

That tape showed that "Columbia was shedding debris, and it was shedding it as it started across the continental United States," Mr. Nelson said.

"But that doesn't mean it's breaking up there, and it doesn't mean that the astronauts were aware that it was shedding debris."

Cif turned her head back toward him and straightened up, bringing the Mouser with her out of the tunnel face and shedding sandy debris.

We've used it in the past when we have shed debris.

The one that broke up was fired southwest toward the Mediterranean, over the Turkish province of Hatay, the ancient Antioch, and shed debris over two villages there.

Work is progressing in areas like redesigning the fuel tank to prevent it from shedding debris at liftoff and techniques to repair damage in space, but those efforts take time, officials said.

Tray covers for use outdoors or in dusty locations may have a peaked shape to shed debris including dust, ice or snow.