US shuttle lifts off on mission to International Space Station

The US space shuttle Discovery roared off on Monday on a 13-day mission to deliver the fourth and final set of power-generating solar array wings and a new Japanese resident astronaut to the International Space Station.

The launch from Cape Canaveral in Florida in clear weather this morning came after almost a month's delay but went off without any trouble.

Discovery's STS-119 flight is carrying the space station's set of solar array wings, completing the station's truss, or backbone. The arrays will provide the electricity to fully power science experiments and support the station's expanded crew of from three to six in May.

The mission features three spacewalks to help install the truss segment to the starboard, or right, side of the station and deploy its solar arrays. The flight also will replace a failed unit for a system that converts urine to potable water.

Shortly before launch, Commander Lee Archambault thanked the teams that helped make the launch possible. "It's truly an honour to be part of this team representing NASA, the nation and the international partners," Archambault said. "See you in a couple of weeks."

Archambault is joined on STS-119 by Pilot Tony Antonelli and Mission Specialists Joseph Acaba, Steve Swanson, Richard Arnold, John Phillips and Japan Aerospace Exploration Agency astronaut Koichi Wakata.

Wakata will replace space station crewmember Sandra Magnus, who has been aboard the station for more than four months. He will return to Earth during the next station shuttle mission, STS-127, targeted to launch in June 2009.

Former science teachers Acaba and Arnold are now fully trained NASA astronauts. They are making their first journey to orbit on the mission and will step outside the station to conduct critical spacewalking tasks.

Discovery's launch was postponed Wednesday after a leak associated with the gaseous hydrogen venting system was detected during fueling.

Technicians rebuilt and replaced seals and other components associated with the system. No leaks were detected during the Sunday's fueling.

The space agency has eight more shuttle mission scheduled to fully commission the International space station, some 360 kilometer above the earth, before retiring shuttle next year.