NASA rejoiced at a successful nighttime landing that capped an exceptionally long — and successful — mission to the international space station.
Endeavour's touchdown Wednesday night on NASA's illuminated runway wrapped up a voyage that lasted 16 days and spanned 6.5 million miles.
Mission Control immediately offered up its congratulations.
"It was a super-rewarding mission," said shuttle commander Dominic Gorie, "exciting from the start to the ending."
NASA's space operations chief, Bill Gerstenmaier, watched with pleasure from the landing strip as Europe's new space station supply ship and then the international space station soared overhead, resembling a pair of twinkling stars.
Moments later, Endeavour landed, an hour after sunset.
"I can't think of a better day, or the better ending of a day, than to see those three wonderful pieces of hardware," Gersteinmaier said.
Endeavour's homecoming was a bit delayed.
The space shuttle was supposed to land before sunset, but at virtually the last minute, clouds moved in.
As the astronauts took an extra swing around the planet, the sky cleared enough to satisfy flight controllers and — after asking Gorie for his opinion — they gave him the green light to head home.
It was only the 22nd space shuttle landing in darkness. Less than one-fifth of all missions have ended at nighttime; the last one was in 2006.
Endeavour blasted off March 11 — also in darkness — on an ambitious, intense space station construction mission that had even its commander wondering at times how everything would go.
In the end, Gorie and his multinational crew accomplished everything they set out to do. The astronauts installed the first piece of Japan's Kibo lab, put together a giant Canadian robot named Dextre, tested a shuttle repair technique and more.
NASA Administrator Michael Griffin said he told Gorie following touchdown that "he had really flown two missions in one for us."
"I can't imagine that the mission could have gone any better, and they made it look easy."
Returning aboard Endeavour was French Air Force Gen. Leopold Eyharts, who spent 1½ months aboard the space station, and Japanese astronaut Takao Doi, who accompanied his country's space station contribution to orbit.
The Japanese Space Agency's vice president, Kaoru Mamiya, said he felt lucky to witness the safe landing of the shuttle.
"It's the first step for our Kibo construction," he said.
The space station is now 70 percent complete, thanks to the latest additions, with a mass of nearly 600,000 pounds.
Ten more shuttle flights to the space station are scheduled over the next two years. NASA hopes to have its share of the orbiting outpost finished in 2010 and its three shuttles retired, so it can focus on human expeditions to the moon.
Discovery is scheduled to fly to the space station in late May, carrying up Japan's enormous Kibo lab.
The fuel tank for that mission arrived at Kennedy Space Center on Wednesday, later than planned, and Griffin said that almost certainly will mean a launch delay of at least a few days.
Subsequent fuel tanks also could get backed up because of all the design changes necessitated by the 2003 Columbia disaster.
NASA expects to have a better idea in another month of whether it can keep the year's launches on track.
On the space station, meanwhile, the three occupants are gearing up for next week's arrival of the European Space Agency's supply ship, Jules Verne.
The unmanned cargo carrier — the first of its kind — rocketed away from French Guiana this month with a load of food, water and clothes.
On April 8, the Russians will launch a fresh space station crew from Kazakhstan.