With the P3/P4 truss securely attached to the International Space Station, STS-115 Mission Specialists Joe Tanner and Heidemarie Stefanyshyn-Piper are now conducting a spacewalk to prepare the bus-sized structure for operation. The spacewalk began at 5:17 a.m. EDT.
The new truss element, which also includes a set of new solar arrays, was attached to the station at 3:48 a.m. Tanner and Piper began their excursion after bolts connecting the P3/P4 to the P1 truss were tightly secured. The third of four bolts was tightened at 4:35 a.m., officially making the P3/P4 a part of the station.
The new 17.5-ton, 45-foot long truss will provide power, data and communication services for the station. The arrays will be unfurled to a full length of 240 feet on Thursday and will eventually double the station’s power capabilities.
Tasks for today’s spacewalk include the installation of power and data cables between the P1 and P3/P4 structures in preparation for solar array deployment. Tanner and Piper will also release launch restraints on the Solar Array Blanket Box and other tasks to configure the structure for upcoming activities.
The excursion is scheduled to conclude at about 11:37 a.m. Mission Specialist Dan Burbank is coordinating the spacewalk activities. Mission Specialist Steve MacLean and Expedition 13 Flight Engineer Jeff Williams are operating the station’s robotic arm, called Canadarm2. During this mission, MacLean became the first Canadian to operate the Canadarm2 in space. Two more spacewalks are scheduled for STS-115.
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