Construction of the International Space Station is one step closer to completion with the addition of the P5 integrated truss structure during Tuesday's spacewalk by STS-116 Mission Specialists Bob Curbeam and Christer Fuglesang.

The spacewalk began at 3:31 p.m. EST and concluded at 10:07 p.m. The P5 was attached to the P4 segment at 5:45 p.m. Mission Specialist Joan Higginbotham used the station's robotic arm to move the new segment with only inches of clearance into its installation position. Then, the spacewalkers guided Higginbotham with visual cues as the exacting operation was carried out.

After the P5?s attachment, Curbeam and Fuglesang finalized the installation with power, data and heater cable connections. They also replaced a malfunctioning camera on the S1 truss. Since they worked ahead of the timeline, Curbeam and Fuglesang were able to tackle some get-ahead tasks.

At the end of the spacewalk, Curbeam congratulated the Nobel Prize winners, including scientist Dr. John C. Mather at NASA's Goddard Space Flight Center in Greenbelt, Md. Mather was honored for his work on the big-bang theory

Two more spacewalks are on tap for STS-116 to reconfigure and redistribute power on the station. The first step of reconfiguring the power will take place Wednesday when the port solar array on the P6 truss will be retracted, which will allow the activation and rotation of the Solar Alpha Rotary Joint on the P4. The rotary joint will allow the solar arrays on the P4 to track the sun.

STS-116?s second spacewalk is set to take place Thursday and the third on Saturday.

No Focused Heat Shield Inspection Required Wednesday

The Mission Control Center in Houston informed STS-116 Commander Mark Polansky that the crew will not need to perform a focused inspection of Space Shuttle Discovery's heat shield on Wednesday.

The STS-116 crew will press ahead with their activities on Wednesday, which includes the retraction of the port solar array on the P6 truss segment.