The Extravehicular Activity, or EVA, is set to begin about 9:40 this morning and is planned to last about 6 1/2 hours. It includes installation of devices to prevent pressure buildup in line fittings; connecting cooling system lines; removing launch restraints from a radiator which will be deployed Sunday, and installing a second camera.
The Spool Positioning Devices (SPDs) are designed to prevent pressure buildup in Quick Disconnect fittings, which could make it impossible to disconnect fittings, if necessary. Sellers and Wolf will install 24 of the devices – most of which are on ammonia lines – during the spacewalk.
Sellers, in the all-white spacesuit, will ride the station's robotic arm to the S1 Truss worksite to hook up nitrogen lines used to pressurize the ammonia system, while Wolf, wearing the suit with red stripes, releases launch restraints on the Crew and Equipment Translation Aid – a handcar on the truss rails. Peggy Whitson, NASA ISS science officer, and Atlantis' Sandy Magnus will operate the robot arm. As with the first spacewalk Thursday, Pilot Pam Melroy will choreograph the EVA from Atlantis' flight deck.
Prior to the spacewalk, Commander Jeff Ashby and Melroy will gently raise the altitude of the station by firing small thrusters on Atlantis. This reboost maneuver will increase the altitude of the complex from 238 statute miles (383 kilometers) to 242 sm (389 km).
Atlantis' crew was awakened at 2:46 a.m. today by the song "Push It," performed by the group Garbage. It was for Sellers, requested by his family. The station crew woke up about 30 minutes later.
Atlantis and station crewmembers are scheduled to go to bed about 7:30 tonight.