Astronauts today installed the International Space Station's final truss segment, Starboard 6, containing the fourth pair of solar arrays. Once the solar array wings are unfurled, the segment will provide the final complement of power to the station.

After station robotic arm drivers John Phillips and Koichi Wakata guided the truss into position, spacewalkers Steve Swanson and Richard Arnold connected bolts to permanently attach S6 to S5. The spacewalkers plugged in power and data connectors to the truss, prepared a radiator to cool it, opened boxes containing the new solar arrays and deployed the Beta Gimbal Assemblies containing masts that support the solar arrays. Mission Control in Houston deployed the radiator, and the stage is set for solar array wing deploy on Friday at 10:58 a.m. EDT.

Today's spacewalk lasted six hours, seven minutes. It was Swanson's third spacewalk and Arnold's first, and the 121st spacewalk in support of station assembly, totaling about 762 hours.

NASA Television will carry a news briefing at 8:30 p.m. with Dan Hartman, Manager, ISS Mission Integration & Operations & IMMT Chair, Kwatsi Alibaruho, STS-119 Lead Space Station Flight Director and Glenda Laws-Brown, Lead Extravehicular Activity Officer for STS-119.

Commander Lee Archambault leads Discovery's crew of seven, along with Pilot Tony Antonelli, and Mission Specialists Joseph Acaba, John Phillips, Steve Swanson, Richard Arnold and Japan Aerospace Exploration Agency astronaut Koichi Wakata on mission STS-119 to the International Space Station.

The STS-119 crew members are flying the S6 truss segment and installing the final set of power-generating solar arrays to the International Space Station. The S6 truss will complete the backbone of the station and provide one-fourth of the total power needed to support a crew of six.