NASA's 30-year shuttle program inched closer to the end Wednesday, wrapping up its next-to-last mission and moving Atlantis to the launch pad for next month's final flight.
Endeavour and its six astronauts returned to Earth after more than two weeks in space, gliding down the runway one last time during a middle-of-the-night landing. A few miles away, Atlantis reached the launch pad at Kennedy Space Center for the grand finale in five weeks.
Endeavour commander Mark Kelly - whose wife, wounded Rep. Gabrielle Giffords, remained behind at her rehab center in Houston - brought Endeavour to a stop before hundreds of onlookers that included the four Atlantis astronauts.
"It's sad to see her land for the last time," Kelly said, "but she really has a great legacy."
Endeavour, the youngest of the shuttles with 123 million miles over 25 flights, is now bound for a museum in California.
A few hours earlier, thousands of employees and their families lined the route Tuesday night as Atlantis slowly crept toward the launch pad, bathed in bright lights.
"We're going to look upon this final mission as a celebration of all that the space shuttle has accomplished over its 30-year life span," Atlantis' commander, Christopher Ferguson, said as he waved toward his ship, which will make the 135th and last shuttle flight.
Endeavour's mission lasted 16 days and completed NASA's role in the space station construction effort that began more than a dozen years ago.
The crew - all experienced spacemen - departed the 220-mile-high orbiting outpost over the weekend. They installed a $2 billion cosmic ray detector, an extension beam and a platform full of spare parts, enough to keep the station operating in the shuttle-less decade ahead.
NASA is leaving the Earth-to-orbit business behind to focus on expeditions to asteroids and Mars. Private companies hope to pick up the slack for cargo and crew hauls to the space station. Until then, Americans will continue hitching rides to the station aboard Russian Soyuz capsules at the cost of tens of millions of dollars a seat.
Kelly was the last astronaut to exit Endeavour. He and his crew posed for pictures and signed autographs on the runway. Astronaut Gregory Chamitoff was so wobbly from weightlessness that he had to be supported by two colleagues, and he later skipped a morning news conference.
As Kelly thanked his crewmates live on NASA TV for their flawless performance, co-pilot Gregory Johnson leaned over to shout into the mic, "And our commander, we want to thank him, too." Johnson and the rest of the crew were openly supportive of Kelly's decision to stick with the flight, despite his wife's serious head injury.
Giffords was shot during an assassination attempt in Tucson, Ariz., in January, but recovered well enough to attend the May 16 launch. The congresswoman did not return to Florida for the landing but Kelly's two teenage daughters were on hand, along with his twin brother, Scott, also an astronaut.
Six hours after the 2:35 a.m. touchdown, Kelly said he hadn't yet called Giffords because of the early hour. "What I'm going to say to her?" he said in response to a reporter's question. "Really miss her and can't wait to get back there tomorrow to see her."
The astronauts will return to Houston on Thursday for a big welcome-home ceremony. Giffords is not expected to attend, said her chief of staff, Pia Carusone, who also confirmed that Kelly called his wife.
Built to replace the destroyed Challenger, Endeavour first soared in 1992 on a satellite-rescue mission that saw a record-setting three spacewalkers grab the wayward craft. Other highlights for the baby of the shuttle fleet: the first repair mission to the Hubble Space Telescope in 1993, to fix its blurred vision, and NASA's first flight to assemble the space station in 1998.
Its final journey featured four spacewalks, the last ones to be conducted by a shuttle crew. One of the spacewalking astronauts, Mike Fincke, set a U.S. career record of 382 days in space.
The flight also marked the first departure of a Russian Soyuz capsule during a shuttle visit to the space station, and the first call to space by a pope. Two Italians were aboard the shuttle-station complex when Pope Benedict XVI phoned from the Vatican.
The official tally for Endeavour, after 19 years of flight, was 170 crew members, 299 days in space, 4,671 orbits of Earth and 122,883,151 miles.
Launch managers marveled Wednesday over how good Endeavour still looks.
"It looks like it's ready to go do another mission," Kelly noted.
Endeavour will eventually head to the California Science Center in Los Angeles. Discovery, the fleet leader which made its final voyage earlier this year, goes to a Smithsonian Institution hangar outside Washington. Atlantis will remain at Kennedy Space Center as a tourist stop, following one last supply run to the space station. Liftoff is set for July 8.
Moving Atlantis to the launch pad as Endeavour touched down helped temper the sadness so many are feeling about the program's end, officials said. Thousands of more layoffs loom.
"We're in the process of transition now, and it's going to be awkward," Atlantis astronaut Rex Walheim said. "But we'll get to the other side and we'll have new vehicles."
But it will be hard to outdo the shuttle, he said as Atlantis rolled to the pad behind him. "I mean, how can you beat that? An airplane sitting on the side of a rocket. It's absolutely stunning."
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