U.S. astronauts Randolph Bresnik and Robert Satcher Jr. completed a five hour, 42 minute spacewalk at 2:06 p.m. EST (1906 GMT) on Monday, which is the third and final spacewalk for
space shuttle Atlantis's STS-129 mission, NASA said.
During the spacewalk, the pair transferred an oxygen filled High Pressure Gas Tank (HPGT) from the EXPRESS Logistics Carrier 2, located on
the starboard truss, to a spot on the outside of the Quest Airlock. The tank, which measures 5 feet by 6.2 feet by 4.5 feet and weights approximately 1,240 pounds, will be used to replenish atmosphere lost when spacewalkers enter and exit the station.
While Satcher completed installation of the HPGT, Bresnik installed the seventh Materials International Space Station Experiment, or MISSE 7. This is the most advanced of the MISSE payloads to date and will be the first to receive power directly from the station and use the station's communication system to send commands and downlink real-time data.
Atlantis lifted off from Kennedy Space Center in Florida on Monday. Its 11-day flight includes three spacewalks and the installation of two
platforms to the station's truss, or backbone. The platforms will hold spare parts to sustain station operations after the shuttles' retirement. The
shuttle will remain at the station until the day before Thanksgiving. Landing would be the day after.
Atlantis' STS-129 mission is NASA's fifth and last shuttle mission for 2009. There are just five more shuttle launches scheduled before the planned
September 2010 retirement of the space shuttle fleet.