Completing one of the most complex repairs in the history of the International Space Station (ISS), Expedition 24 flight engineers Doug Wheelock and Tracy Caldwell Dyson began re-pressurizing the Quest airlock at 12:40 p.m. CDT, marking the end to the 150th spacewalk devoted to ISS assembly and maintenance since 1998.
During their seven hours and 20 minutes outside, Wheelock and Caldwell Dyson relocated, secured and ran cables to a spare pump module, replacing the 780-pound unit that failed on July 31 and was removed during two prior spacewalks last week. The spacewalkers' work will lead over the next couple of days to the restoration of the station's Loop A cooling system.
"We got our station back," said Wheelock, after hearing from Mission Control that the pump was "looking good."
The astronauts had planned to get to one "get-ahead" task, attaching a cable extension from Quest to an existing power cable on the Unity node to avoid interference when the Permanent Multipurpose Module is added during the STS-133 mission in November. Running short on time however, flight controllers decided to defer that activity to a later spacewalk.
Today's spacewalk was the sixth for Wheelock, who with a total of 43 hours and 30 minutes accumulated now ranks tenth in the world for time spent working in the vacuum of space.
This was Caldwell Dyson's third spacewalk. It was the 242nd by U.S. astronauts and the 339th in history.
During the course of the space station's 150 spacewalks, astronauts and cosmonauts have spent 944 hours and 24 minutes outside since the first ISS-devoted excursion in December 1998.