NASA officials say no fuel tank debris was observed hitting Discovery during Friday's midnight liftoff. But the shuttle's most vulnerable areas - the wings and nose - still needed to be checked with lasers and cameras on a boom attached to the robot arm.
In addition, the shuttle's underside will be photographed in detail by the space station residents Sunday night, right before the two craft meet.
A hole in the wing brought down Columbia six years ago. Ever since, NASA has been vigilant in seeking out indications of serious launch damage.
Discovery is loaded with supplies for the space station, now home to six astronauts. Once the seven shuttle fliers arrive, it will make for a record-tying crowd.
"It's great to be back in space," Discovery's commander, Rick Sturckow, said Saturday afternoon.
"Micro G is great," rookie astronaut Jose Hernandez noted in his first Twitter update from space. The Mexican-American grew up in a migrant worker family and applied for 12 straight years to become an astronaut, before getting picked in 2004. "Settling in and realizing my dream," he wrote.
Discovery's supply run will leave the space station well stocked; the shuttle is hauling about 17,000 pounds of equipment and science experiments. Six mice, part of a bone loss study, will move in for a three-month stay. So will astronaut Nicole Stott, the replacement for an astronaut who has been at the orbiting complex for more than a month.
Stott will help put together a brand new $5 million treadmill flying up on Discovery that will expand the space station's gym. The treadmill, currently in more than 100 pieces, is named after Comedy Central's Stephen Colbert. Earlier this year, he won an online vote for naming rights to a space station room, but NASA picked the name Tranquility instead and offered him the running machine.
The launch of the COLBERT treadmill - officially the Combined Operational Load Bearing External Resistance Treadmill - was mentioned prominently on the Colbert Nation web site Saturday.
"The universe just got a little bit slimmer," a headline teased. The workout machine won't see action anytime soon. Stott and her station roommates won't have time to assemble it until sometime after the mid-September arrival of a new Japanese cargo ship.
Discovery, meanwhile, was reported to be in good flying shape aside from a leaky thruster. The astronauts were advised to shut down the thruster - as well as a companion thruster in the nose - for the rest of the 13-day flight. Officials said it should have no impact on the mission.
Colbert Nation: http://www.colbertnation.com/home