After Weather Delay, Discovery Lands Safely

The space shuttle Discovery landed at Kennedy Space Center at sunset yesterday, ending a 13-day mission to further assembly of the international space station.

The late-afternoon landing on a floodlit runway came after a two-hour, one-orbit delay, caused by cloudy conditions in Florida. The landing was smooth, and the crew appeared to be in good health.

Discovery's return completed NASA's third successful shuttle flight of 2006, the most since 2002. After the Columbia disaster that killed seven astronauts in February 2003, the space agency redesigned the shuttle's fuel tank, changed safety procedures in space and set out to finish assembly of the half-built international space station.

"Congratulations on what was probably the most complex assembly mission to date," astronaut Kenneth T. Ham, at Mission Control in Houston, radioed to the crew as the shuttle came to a stop.

"You've got seven thrilled people right here," commander Mark L. Polansky replied.

The Florida landing was a pleasant surprise to NASA managers, who were concerned that bad weather would require a landing at Edwards Air Force Base in California -- where strong crosswinds can pose problems -- or White Sands Space Harbor in New Mexico, where a shuttle has not landed since 1982. It can take weeks or months to transport the shuttle back to Florida, and that delay could have affected NASA's plan to send 13 more missions to the space station by 2010.

"If you were to ask me before the flight what I wanted for Christmas, what I wanted was a safe and successful shuttle flight," said William H. Gerstenmaier, NASA associate administrator for space operations, the Associated Press reported. "This is just a tremendous way to end this year."

Although Russian spaceships regularly bring crew members and supplies up to the station, only the 112-ton space shuttle has the size and power to carry up the larger components of the station.

While at the station, the Discovery crew continued assembly of the facility and its laboratory. It added an additional truss segment, rewired the station's power system and worked to refold a solar panel that had folded up improperly.

Discovery also delivered a new crew member, American Sunita L. Williams, and more than two tons of equipment and supplies to the station, most of which were located in the Spacehab cargo module. Williams took the place on the station of German astronaut Thomas Reiter, who had been in space since July.

The Discovery mission featured a NASA first: four spacewalks by one astronaut during a mission. Baltimore native Robert L. Curbeam, 44, was in open space on four of the seven days the shuttle was at the space station. His time outside of Discovery, combined with the time he spent in space on a 2001 mission, put Curbeam in fifth place among all astronauts in the amount of time spent on spacewalks.

The first Swede in space, Christer Fuglesang, participated in three spacewalks.

The next shuttle mission is scheduled for late February.