Shuttle inspects heat shield on way to space post

By Chris Baltimore

HOUSTON (Reuters) - Astronauts orbiting the Earth aboard the U.S. space shuttle Endeavour unfolded a robotic arm on Saturday to inspect the ship's heat shielding as they sped toward a rendezvous with the International Space Station.

After the seven astronauts soared skyward on Friday night from NASA's seaside launch pad in Florida, their main priority on Saturday was inspecting the ship's wings and nose for possible damage using a robotic arm.

The tedious inspection has been standard practice since the 2003 Columbia disaster, when debris from the shuttle's external fuel tank knocked a hole in its wing, causing the craft to disintegrate as it entered the Earth's atmosphere, killing all seven astronauts aboard.

Endeavour's flight was NASA's first launch in nearly six months and the 124th in shuttle program history. Just nine more launches remain before NASA is scheduled to mothball the shuttles so it can develop safer and less expensive spaceships that will return astronauts to the moon.

NASA must first complete construction of the $100 billion, 220-mile-high space station, a project of 16 countries. Endeavour is slated to dock at the station on Sunday afternoon.

Endeavour's flight is intended to outfit the station for six full-time residents. It has been operating with half that number since assembly began a decade ago.

The shuttle carries two new sleeping compartments and a water recycling system so station crew members can purify urine and other wastewater for drinking.

Friday's moonlit launch was mostly routine, except for a door that was left unlatched on the launch platform next to the shuttle. NASA officials said the lapse did not threaten the shuttle's safety.

On Saturday morning, NASA controllers at Johnson Space Center in Houston told shuttle commander Chris Ferguson that they had spotted a small tear in the insulation around a steering jet near the rear of the ship that would need to be inspected.

"OK, I have an idea where that is," Ferguson said. NASA officials said the inspection was not urgent, and could possibly be completed after Endeavour detaches from the space station -- now scheduled for November 27, with a landing in Florida slated for November 29.

NASA planners say they will likely add an extra day to the mission to allow astronauts to perform checks on the water purification system.

The nine remaining flights will include a final servicing call to the Hubble Space Telescope. NASA is preparing to end the program in 2010, after which Russian Soyuz spacecraft will be the only way to ferry crew to the space station.

(Additional reporting by Irene Klotz in Cape Canaveral, Florida; Editing by Peter Cooney)