NASA Zeroes In On Three Damaged Tiles

NASA photo-analysts are taking a close look at three areas where heat-shield tiles on the underside of shuttle Endeavour sustained damage during launch or flight to the International Space Station.

It's unclear at this time whether the astronauts might have to make a follow-up focused inspection later this week.

But NASA managers say they are not worried about the shuttle or its six-member astronaut crew.

"This is not cause for alarm or concern," LeRoy Cain, NASA's deputy shuttle program manager and chairman of its Mission Management Team, said in a news briefing today. "At this point we don't have any reason for concern or alarm."

Damage to thermal tiles on the underside of the shuttle is not uncommon. However, if it is severe enough, it could endanger a shuttle and its crew when extreme temperatures -- up to 3,000 degrees Fahrenheit -- are encountered during atmospheric reentry.

Endeavour's tile damage all was done near sensitive areas where seals potentially could be breached during reentry. High-resolution photos taken today before the shuttle's final approach to the station detailed the trouble spots.

An engineering analysis is underway at Johnson Space Center in Houston as well as other sites around the country.

NASA always books a half-day during the sixth day of a shuttle mission to perform focused heat-shield inspections if necessary. A decision to do an additional look would be made by Friday at the latest.

The photographs were taken from the inside of the station's Russian Zvezda core module by U.S. astronaut Cady Coleman and Italian astronaut Paolo Nespoli.

Shuttle skipper Mark Kelly guided Endeavour through a back-flip designed to point the shuttle's belly toward the outpost. The eight-minute maneuver has been standard operating procedure since undetected heat-shield damage led to the 2003 Columbia accident.