Mission Specialists Jim Reilly and Danny Olivas worked outside the station for 7 hours, 58 minutes and completed all their planned tasks. Olivas spent two hours stapling and pinning down a thermal blanket on Atlantis’ orbital maneuvering system pod. A 4-by-6-inch corner of the blanket peeled up during the shuttle’s launch last week.
Meanwhile, Reilly installed the hydrogen vent valve of a new oxygen generation system on the Destiny laboratory. The system will separate oxygen from water to provide breathing air, while dumping the remaining component – hydrogen – overboard.
When those tasks were completed, the two astronauts joined forces with their colleagues inside the shuttle and station and flight controllers in Houston to complete the delicate process of folding an older solar array so that it can be moved from its temporary location to its permanent home during a shuttle mission this fall.
Armed with lessons learned from last December’s shuttle mission when the other half of the array posed an identical challenge, the STS-117 mission team followed well-trained procedures to retract the array into its protective box. The retraction was completed and latches closed at 7:40 p.m. (7 hours, 15 minutes into the spacewalk). Reilly and Olivas provided hands-on assistance throughout the process.
The retraction sequence today required 28 commands, bringing the total for the retraction to 45.
Behind the scenes while the spacewalk was ongoing, Russian flight controllers were troubleshooting two Russian computers that provide backup attitude control and orbital altitude adjustments for the station’s control moment gyroscopes. Station commander Fyodor Yurchikhin and Flight Engineer Oleg Kotov were able to get two of three lanes in both computers up and running after bypassing with external cabling what appeared to be a faulty power switch.
The computers are now being monitored for proper operation, awaiting additional data evaluation overnight when the station passes over Russian ground stations for detailed telemetry downlink. Each computer requires only one lane running to perform its duties.
One final spacewalk is planned for Sunday, when Mission Specialists Patrick Forrester and Steve Swanson will perform get-ahead tasks and finish preparing the Solar Alpha Rotary Joint for activation. Its function is to allow a new pair of solar arrays to track the Sun as the station circles the Earth.
The crew will spend part of Saturday getting ready for the last spacewalk and discuss the mission during the traditional news conference at 6:43 p.m.