Spacewalkers Prep SARJ for Action
Image: Spacewalker Pat Forrester rides on the end of the station’s robotic arm to assist with the retraction of a solar array. Image credit: NASA TV
Astronauts Patrick Forrester and Steve Swanson continued work to activate the International Space Station’s Starboard 3 and 4 (S3/S4) truss segment during STS-117’s second spacewalk. The 7-hour, 16-minute excursion wrapped up at 9:44 p.m. EDT Wednesday. Meanwhile, managers approved a repair task for a damaged thermal blanket to be carried out during the next spacewalk Friday.
The spacewalking duo first assisted with the retraction of the starboard solar array on the Port 6 (P6) truss. They left launch restraints still attached on the S3/S4 Solar Alpha Rotary Joint (SARJ). Flight controllers want to take a closer look at a drive lock assembly on the SARJ. After the launch restraints are removed on an upcoming spacewalk, the rotary joint will allow the S3/S4 arrays to track the sun as the station orbits Earth.
13 of the P6’s 31.5 array bays were retracted Wednesday, and the crew will send commands Thursday to retract the remaining bays. Before moving on to SARJ, Forrester and Swanson “fluffed” the array to allow easier retraction on Thursday.
The retraction of the P6 array clears the line of sight for the S3/S4 arrays to track the sun and sets the stage for the P6’s relocation by a future shuttle crew from atop the station to the end of the Port 5 truss.
Mission Specialist Jim Reilly coordinated the spacewalk, and Pilot Lee Archambault operated the station’s robotic arm. Two more spacewalks are scheduled for STS-117. The next is set for Friday.
In other activities, Expedition 15 Commander Fyodor Yurchikhin and Flight Engineers Oleg Kotov and Clayton Anderson continued to transfer cargo between the station and Space Shuttle Atlantis.
Russian flight controllers will be working overnight to resolve a problem with the Russian segment computers that provide backup attitude control and orbital altitude adjustments. For now, the station’s control moment gyroscopes are handling attitude control, with the shuttle’s propulsion providing backup.
