A small gouge in space shuttle Endeavour's heat shield appears to be a minor problem and is unlikely to require repair, NASA said on Saturday after studying the three-inch (8 cm) gash on the ship's belly.
The shuttle crew will use remote sensors on Endeavour's robot arm to take a closer look on Sunday, but mission management team chairman John Shannon said there "are very good signs this will not be something we'll have to worry about."
NASA, which discovered the gouge on Friday from photographs taken as Endeavour arrived at the International Space Station, feared it might have to be patched by spacewalking astronauts to ensure the shuttle's safe return to Earth.
Shannon said in a briefing at Johnson Space Center that video showed a grapefruit-sized piece of insulating foam broke free from Endeavour's fuel tank and struck the ship as it launched from Florida on Wednesday.
But the damage appears to be superficial and is in a place where the fiery heat of the return to Earth would not threaten the shuttle, Shannon said.
A final decision on the need for repairs will not be made until after Sunday's inspection.
Initially, NASA thought Endeavour might have been hit by ice, which is denser and potentially more destructive than foam.
Debris flies from shuttles at every launch, but the US space agency has taken steps to curb the problem since shuttle Columbia disintegrated while returning to Florida in 2003, killing the seven astronauts on board.
That accident was blamed on a briefcase-sized piece of flying tank foam that struck Columbia's wing during launch and put a sizable hole in the heat shield.
The damage went undetected, which is why NASA now conducts at least three damage inspections during each flight, including the photos taken by the station crew as the shuttle approaches for docking.
The shuttle is covered with ceramic heat-resistant tiles and carbon panels to protect its aluminum skin from melting during the plunge back through the atmosphere for landing. Temperatures around the damage site can reach up to 2,000 degrees Fahrenheit (1,093 degrees Celsius).
NASA officials also had good news about the main US computer on the space station, which suddenly crashed on Saturday, forcing backup computers to take over.
Station flight director Joel Montalbano said the crash appeared to be a software problem and, after trouble-shooting , the computer would be returned to operation.
While NASA dealt with the two problems on Saturday, astronauts Rick Mastracchio and Dave Williams completed the main task of Endeavour's mission by bolting a new beam on to the space station during a six-hour spacewalk.
Installation of the 11-foot (3.4-metre) and two-tonne aluminum extension was another step toward planned completion of the $100 billion international project by 2010.
Endeavour is scheduled to return to Earth on Aug. 19 but NASA has said it may extend the mission by three days.
The shuttle crew includes teacher-turned-astronaut Barbara Morgan, the backup to fellow teacher Christa McAuliffe, who died in the 1986 after-launch explosion of shuttle Challenger.
Last Mod: 12 Ağustos 2007, 17:55