NASA Gives Shuttle The All-Clear To Return
A metal clip fell from Discovery's brakes on Friday but NASA said it won't delay the space shuttle's scheduled landing on Saturday.
The astronauts reported to Mission Control earlier Friday that they saw a rectangular object, about 1 to 1½ feet long, floating away from the tail of the shuttle. It turned out to be one of three metal clips around thermal insulation.
The insulation is in the shuttle's rudder speed brake, which is used to slow the spacecraft as it comes in for a landing.
NASA says the missing clip isn't critical for landing. It's used to protect the speed brake from high temperatures during the shuttle's launch.
"Orbiters have come back with those missing. It's just not a factor for entry," Mission Control told the shuttle crew.
In an interview with CBS News space consultant Bill Harwood Shuttle Commander Mark Kelly said, "we've seen these things before... it's not a concern at all for re-entry."
Discovery's crew had also reported seeing something sticking out from the left side of the shuttle's rudder. But Mission Control said it was probably just an optical illusion because of the rudder's angle, and the area looks the same as it did before the shuttle launched.
"There's no issue with that," Mission Control said.
Discovery's crew of seven is returning from the international space station after delivering and installing a new science lab. The shuttle is scheduled to land at 11:15 a.m. EDT Saturday in Florida.
On Thursday, the shuttle's heat shield was given a preliminary thumbs up for the return trip to Earth after engineers finished scrutinizing all the images of it on the wing and nose, which were collected Wednesday with a laser-tipped inspection boom.
"Looks like you have a clean orbiter," Mission Control radioed the shuttle astronauts.
Discovery's heat shield was expected to be given formal clearance for landing during the mission management team's meeting Friday afternoon. Discovery is scheduled to land at 11:15 a.m. EDT Saturday in Florida.
The thermal survey - an exhaustive search for damage - was conducted later than usual because the astronauts had to wait until they got to the space station to retrieve their inspection pole. There was not enough room aboard Discovery for the pole at liftoff because the Japanese lab the shuttle delivered to the space station had taken up nearly all the room in its payload bay.
The inspection is one of the safety measures put in place by NASA after the 2003 Columbia accident. Columbia was destroyed during re-entry as a result of a gashed wing.
Discovery's crew of seven installed the new lab named Kibo, Japanese for hope, to the space station.
Read CBS News space consultant Bill Harwood's lastest Shuttle status report.
Besides delivering the new lab, the shuttle also dropped off Gregory Chamitoff, the station's newest crew member. He traded places with Garrett Reisman, who lived on the station for three months. Chamitoff will stay on the station for six months.
"We had a very successful shuttle mission, with the Japanese module attached. It's a very big facility now," Chamitoff told German President Horst Kohler on Friday morning during a call between the space station's three-man crew and German officials.
The 37-foot lab, about the size of a bus, is the biggest room at the space station. Kibo also has a storage closet and a 33-foot robotic arm. A final section - a "porch" for exterior experiments - and a second, smaller robotic arm will be delivered next year.
Discovery also brought a pump that fixed the space station's malfunctioning toilet. The problem had forced the station's crew to flush manually with extra water several times a day.
On Friday, NASA continued investigating what caused extensive damage at the launch pad used to shoot Discovery into orbit two weeks ago.
About 5,300 bricks flew off the pad during the May 31 launch, exposing a thick concrete wall underneath. The pad was built for the Apollo moon shots, and the bricks might not have adhered properly to the wall of the flame trench when they were installed in the 1960s, said LeRoy Cain, chairman of the mission management team.
The flyaway bricks posed no danger to Discovery, but NASA wants to fix the flame trench - designed to deflect the exhaust of the booster rockets - so it does not get worse. Cain said he's confident it will be repaired in time for the next shuttle flight in October.