Among the goodies awaiting the space station crew were a new stationary bicycle for exercise, an oxygen generator that will eventually allow the space station to support six inhabitants, a machine that cools the station's cabin air and a lab freezer for scientific samples.
Unloading items 220 miles above Earth was even more difficult than moving into a house since at least there's gravity on the ground, Steve Lindsey, Discovery's commander, said in interviews with reporters on the ground.
"It's really kind of a challenge because you're in zero-G ... you've got to go very, very slow because if you go fast, you kind of run into things and bump into other equipment," Lindsey said. "It's kind of an interesting choreography we have to go through."
For the first time in three years, the space station has three crew members — European Space Agency astronaut Thomas Reiter on Thursday joined Pavel Vingogradov and Jeff Williams, who marked their 100th day at the space station Friday.
Discovery's six remaining shuttle crew members awoke Friday to a recording of The Beatles' "Good Day Sunshine," a choice of astronaut Lisa Nowak's family.
Flight controllers also told Discovery's crew that they expected NASA managers on Friday to extend the mission by a day to allow for a third spacewalk. That would bring the mission to 13 days.
The robotic arm and boom were used two days ago to examine the shuttle's nose cap and wings for damage. Before docking Thursday, Lindsey maneuvered the shuttle into a back flip so that the space station's crew could photograph the shuttle's belly and transmit to the images to engineers in Houston.
CBS News Space Consultant Bill Harwood reports one area of concern involves three gap fillers seen protruding above the surface of surrounding heat-shield tiles on the shuttle's belly. One is toward the edge of the shuttle's left wing, another is near a propellant feedline access door and the third (assuming it actually is a gap filler) is located just behind Discovery's reinforced carbon carbon nose cap.
Gap fillers are thin, ceramic cloth spacers used to smooth the flow of air across the gaps between tiles and to prevent adjacent tiles from rubbing against each other too much during the vibration and stress of launch. The gap fillers are bonded in place, pull tested before launch and their upper surfaces are flush with the surrounding tiles.
Gap fillers occasionally shake loose and extend up into the airflow during re-entry and disrupt the smooth, laminar flow of supersonic air across the belly of the shuttle. Known as "tripping the boundary layer," this phenomenon can create eddies of turbulence that, in turn, result in higher downstream heating.