The space shuttle Discovery, high above Earth, is on schedule for its linkup in orbit with the International Space Station Thursday.
As the 125-ton spacecraft approaches the space station, the astronauts aboard will steer it into a slow-motion backflip. Crewmen in the space station will take detailed photographs of the shuttle's heat shield, checking for any damage during Discovery's launch on Tuesday.
Shuttle astronauts already have inspected the orbiter's outer surface with a 15-meter boom fitted with a camera and laser. Although the examination is not yet complete, U.S. space agency officials say nothing of major concern has been discovered.
Video recordings of Discovery's exterior during the first few minutes after blastoff showed five pieces of debris -- probably foam insulation -- falling off an external fuel tank, but NASA says that has not raised safety concerns.
Meticulous inspections and examinations of space shuttles have been routine since the Columbia disaster in 2003, when that spacecraft broke apart and burned during its high-temperature flight through Earth's atmosphere, killing all seven men and women aboard.
Investigators concluded the calamity was caused by a large piece of foam insulation that damaged Columbia's heat shielding during liftoff.
Discovery is carrying supplies up to the International Space Station and delivering a German astronaut Thomas Reiter who will remain abord the orbiting laboratory for an extended visit.
Two of the shuttle's seven crew members Piers Sellers and Michael Fossum are scheduled to perform at least two spacewalks during the 12-day mission.
