Astronaut Sunita L. Williams, Expedition 14 flight engineer, uses a pistol grip tool (PGT) as she participates in the first of three sessions of extravehicular activity (EVA) in nine days, as construction continues on the International Space Station. During the 7-hour 55-minute spacewalk, Williams and Michael E. Lopez-Alegria (out of frame), commander and NASA space station science officer, reconfigured one of two cooling loops for the Destiny laboratory module, rearranged electrical connections and secured the starboard radiator of the P6 truss after retraction.