First Battery Replaced

At 11:17 a.m. EDT, STS-127 Mission Specialists Chris Cassidy and Tom Marshburn replaced the first of four batteries they plan to exchange during today’s spacewalk. They just completed releasing the fourth old battery from its location on the space station’s Port 6 truss.

An hour and 35 minutes into the spacewalk, they are on the planned timeline and their spacesuit consumable levels are normal.

Battery Replacements During Fourth Spacewalk

STS-127 Mission Specialists Chris Cassidy and Tom Marshburn will tackle a challenging 7 ½-hour spacewalk today to finish swapping out batteries for the International Space Station’s oldest set of solar arrays.

Their outing will be devoted entirely to finishing the work started on the third spacewalk of the mission – removing old batteries from the Port 6 truss structure and transferring new batteries from the Integrated Cargo Carrier on the end of the station’s robotic arm to the empty sockets on the truss.

Pilot Doug Hurley and Mission Specialist Julie Payette will position Canadarm2 near the truss for the spacewalk and, once all of the battery swaps are complete, maneuver the carrier back into Endeavour’s cargo bay. That maneuver will require them to hand off the carrier to the shuttle’s arm for re-berthing by Hurley and Commander Mark Polansky.