All efforts pointed toward the deployment and installation of the Starboard One (S1) Truss. Pilot Pam Melroy, Space Station Commander Valery Korzun, and Mission Specialists Dave Wolf, Piers Sellers, and Fyodor Yurchikhin configured the spacesuits for Thursday's spacewalk. Mission Specialist Sandy Magnus and NASA ISS Science Officer Peggy Whitson reviewed robotic arm operations for moving the new truss segment into place. Sergei Treschev, ISS Flight Engineer, participated in the safety briefing for the station visitors.
Thursday, Magnus and Whitson will use the Canadarm2 from inside Destiny to grapple the huge S1 Truss, take it out of Atlantis' payload bay and move it into position at the starboard end of the S0 Truss. After the segments are soft-mated, capture bolts will make the mating solid. With the truss firmly attached to the station, the spacewalkers will exit the station.
Tomorrow's EVA begins three days of spacewalks – Thursday, Saturday and Monday - at the station-shuttle complex. Shuttle and Mir veteran Wolf and space rookie Sellers will perform the EVAs, which are primarily focused on the installation and hookup of the S1 segment. In Thursday's six-hour spacewalk, Wolf and Sellers will connect power, data and fluid umbilicals between the segments; install a camera and antenna assembly; and release a number of launch restraints. Wolf will ride on the end of the robotic arm for most of the excursion, while Sellers will be a "free floater" moving around the truss structure.
Tonight the crew is scheduled to begin its sleep period at 6:46 p.m. with the wake-up call to sound at 3:16 a.m. Thursday.