A pair of spacewalking astronauts left the international space station to install a new cooling unit which was brought up last week by the space shuttle Discovery.
Discovery astronauts John Danny Olivas and Christer Fuglesang (European Space Agency) began the 132nd spacewalk in support of space station construction at 6:12 pm EDT this evening.
This second of three planned orbital walks in space is focused on the installation of a new ammonia tank and the stowage of the old tank which was removed from station on Tuesday evening during the first spacewalk.
Shortly, Fuglesang will strap his boots into the end effector of the space station's robotic arm for a 30 minute ride as he carries the 1700 pound ammonia tank, while orbiter pilot Kevin Ford steers the arm from inside the Destiny module of station.
The pair will begin installing the new tank at about 8PM, and will later place the old tank in Discovery's bay for the return trip home. Once back on earth, the Johnson Space Center told this reporter last night that it will be refurbished and placed back in Discovery's payload bay for it's relaunch on the March 2010 STS-131 station resupply mission.
Discovery's crew includes commander Rick "CJ" Sturckow, pilot Ford, and mission specialists Jose Hernandez, Patrick Forrester, Olivas, Fuglesang and former station expedition 20 member Tim Kopra.