Live in orbit: P6 now permanently placed

Seven years after its delivery to the International Space Station, the P6 solar array truss now is in its permanent position at the far left end of the outpost's central truss.

The placement came at 7:10 a.m. EDT after spacewalking astronauts Scott Parazynski and Douglas Wheelock finished fastening four corner bolts that connect the P6 to outboard port end of the truss. It marked the end of an unprecedented move from its previous home atop the U.S. Unity module, where it served as the prime station power-generator during the early stages of outpost assembly.

The move from its initial base atop the Z-1 truss involved a highly choreographed sequence that involved both the station and shuttle robot arms as well as the high-tech rail cart that runs along tracks on top of the central truss. The P6 was snatched from atop Unity with the station crane and handed off to the shuttle's robot arm. Then rail cart the transported the station arm out to a point near the portside end of the central truss. Finally the station arm grabbed the 17.5-ton girder again and mounted it to the far left end of the central truss.

From start to finish, the move took five days and three spacewalks to complete.

Still to come: the planned unfurling of the two massive solar wings at the end of the truss - a job critical to paving the way to the planned Dec. 6 launch of shuttle Atlantis and the European Columbus science laboratory.

That mission and station assembly cannot continue until the wings are deployed at 11:58 a.m. EDT and 12:58 p.m. EDT today. You can watch the action unfold here in The Flame Trench. Simply click the link below the image above to launch our NASA TV viewer and round-the-clock coverage of NASA's 120th shuttle mission.

The timing of all major mission milestones are listed in the latest version -- Rev F -- of the NASA TV schedule: tvsked_revf.pdf.

Parazynski and Wheelock, meanwhile, remain busy outside the station. They are removing shrouds that provided thermal protection to the Sequential Shunt Unit on the P6 truss. They'll release a cinch on a truss radiator so it can be deployed about 10:18 a.m. EDT. They'll haul a spare Main Bus Switching Unit from Discovery's cargo bay to an external stowage platform attached to the Quest airlock and they'll inspect the station's portside rotary joint as part of an investigation into trouble with an identical joint on the starboard side of the outpost.

Now three hours into a planned seven-hour spacewalk, Parazynski and Wheelock are about a half-hour ahead of schedule.