Walheim during EVA 1

S122-E-007828 (11 Feb. 2008) --- Astronaut Rex Walheim, STS-122 mission specialist, participates in the first scheduled session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the almost eight-hour spacewalk, Walheim and astronaut Stanley Love (out of frame), mission specialist, installed a grapple fixture on the Columbus laboratory and prepared electrical and data connections on the module while it rested inside Space Shuttle Atlantis' payload bay. The crewmembers also began work to replace a large nitrogen tank used for pressurizing the station's ammonia cooling system.