The third spacewalk of Endeavour’s visit to the International Space Station will help lay groundwork for relocation of the Port 6 truss, upgrade a station voice communications system and retrieve materials experiments.

Endeavour Mission Specialist Rick Mastracchio and station Flight Engineer Clay Anderson are scheduled to begin the 6½-hour spacewalk at 10:01 a.m. CDT.

The Endeavour crew, Commander Scott Kelly, Pilot Charles Hobaugh, and Mission Specialists Tracy Caldwell, Mastracchio, Dave Williams, Barbara Morgan and Alvin Drew, and station crew members, Commander Fyodor Yurchikhin, Flight Engineer Oleg Kotov and Anderson, were awakened for spacewalk 3 day at 5:07 a.m. CDT by “Good Morning World.” It was written and performed by Morgan’s son Adam.

The station’s P6 truss is to be relocated from atop the Unity node to the left end of the main truss. Spacewalkers will move two Crew Equipment Translation Aid (CETA) carts from tracks on the left side of the Canadarm2’s mobile transporter to its right side. That will clear the way for the arm to work on the P6 relocation, scheduled during the next shuttle mission.

Mastracchio and Anderson also will relocate an antenna base and install a new transponder and signal processor in an S-band communications upgrade.

The spacewalkers will retrieve two experiments for return to Earth. The materials experiments, dubbed MISSE (for Materials International Space Station Experiment) 3 and 4, could play a role in construction of future spacecraft. These are the last two of five suitcase-like containers exposing hundreds of material samples to the harsh conditions of space for about a year. These were deployed in August 2006. MISSE 1, 2 and 5 already have been returned to Earth.

Transfer operations, movement of supplies, equipment and other material between Endeavour and the station, also will continue. It is about half complete.

The next status report will be issued Wednesday evening or earlier if events warrant.

News from Commercial Space Watch