Two astronauts from the crew of the space shuttle Endeavour have conducted a successful spacewalk Wednesday. NASA engineers on the ground are finishing up tests to decide whether a fourth spacewalk might have to be devoted to repairing damage to the spaceship's heat-shield tiles.  VOA's Cindy Saine reports from Washington.

Flight Engineer Clay Anderson holds a Crew Equipment Translation Aid cart during the third spacewalk, 15 Aug 2007

Spacewalkers Rick Mastracchio and Clayton Anderson ventured outside the International Space Station to prepare the orbital laboratory for future construction.  The astronauts successfully moved two equipment carts to the starboard side of the space station's railcar-like Mobile Transporter.

NASA cut the spacewalk short after Matracchio noticed a hole in the outer layer of his glove.  Mission Control stressed that the astronaut was in no danger, and that the hole did not penetrate all the layers of his glove.  But he was ordered back into the airlock as a precaution, as his partner Anderson wrapped up the work outside.

On the ground, NASA experts were evaluating whether astronauts should fix a deep gash on the underside of the spaceship. Agency officials say a piece of foam insulation broke off the fuel tank and struck the shuttle during launch, causing the damage.

John Shannon, the chairman of the mission management team, said the gouge does not present any threat to the crew's safety.  He said tests are still continuing, but preliminary results indicate the Endeavour will be safe to fly back home next week without repairs.

"We are cautiously optimistic that we can fly as is," he said.

Shannon said he is confident crewmembers can perform any necessary repairs, since they have trained extensively for such missions.