The shuttle Discovery backed away from the international space station and started a two-day journey home on Tuesday after its crew bade farewell to the station's residents and left behind US astronaut Suni Williams for a six-month stay. Discovery is scheduled to return to Earth on Friday after a 13-day flight.
Discovery will stay about 46 miles (74 kilometers) from the station for an inspection of its heat shield Wednesday, allowing the astronauts to return to the space lab in case damage is found. Although they did not expect a problem, flight controllers were keeping an eye on two items lost during the mission's four spacewalks that are now space junk a 7-inch (18-centimeter) long socket and a camera because of the small chance they could hit the shuttle.
During eight days at the space station, Discovery's astronauts made four spacewalks, during which they rewired the station's power system, installed a 2-ton (1.8-metric ton) addition and coaxed a stubborn solar panel to fold up into its box.
"It's always a goal to try and leave some place in a better shape than it was when you came," said Discovery commander Mark Polanksy. "And I think we've accomplished that." The fourth spacewalk to fix the jammed solar panel was added at the last moment. That extended the mission by one day and put astronaut Robert Curbeam in the history books, with a record four spacewalks in a single shuttle mission.
Williams becomes the newest member of the three-person space station crew. Discovery is bringing home her predecessor, German astronaut Thomas Reiter, who spent six months in orbit. During the farewell ceremony before the two crews parted, Williams playfully nudged Reiter into the shuttle using her floating foot.
American space station crewman Michael Lopez-Alegria saluted the departing Reiter for his "competence, conscientiousness and consistency" and pronounced him a "model astronaut." "By the authority vested in me, which I just invented, we would like to make you an honorary member of the NASA astronaut corps," Lopez-Alegria said, pinning wings onto Reiter's shirt.