Image above: The International Space Station's robot arm moves the Japanese Pressurized Module from space shuttle Discovery's payload bay to its new home on the station. Photo credit: NASA TV

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STS-124 completes first spacewalk

The crews of space shuttle Discovery and the International Space Station wrapped up a busy day Tuesday, completing a six-hour, 48-minute spacewalk and expanding the Japanese segment of the orbital outpost.

Mission specialists Mike Fossum and Ron Garan completed STS-124’s first spacewalk at 7:10 p.m. EDT. During the excursion, the pair retrieved a shuttle inspection tool, serviced and inspected components of a solar alpha rotary joint and prepared the largest component of the Japan Aerospace Exploration Agency’s Kibo laboratory for installation on the International Space Station.

The spacewalkers first transferred the Orbiter Boom Sensor System (OBSS) from the station’s truss to space shuttle Discovery. The OBSS, which attaches to the shuttle’s robotic arm for detailed inspection of the shuttle’s heat shield, was left at the station during the previous shuttle mission to provide room for the giant Kibo module in Discovery’s payload bay.

Image above: A view of the Japanese Pressurized Module as it moves from space shuttle Discovery's payload bay to its new home on the station. Credit: NASA TV

Next, the spacewalkers prepared Kibo’s Japanese Pressurized Module (JPM) for installation. After inspecting the common berthing mechanism on the Harmony Node’s left side and opening a window cover, Fossum and Garan worked together in the shuttle’s cargo bay to remove contamination covers from the JPM’s docking surfaces. Fossum also disconnected heater cables and removed locking bolts from the shutters of the JPM’s forward window.

For their final tasks, Garan and Fossum moved to the station’s starboard solar alpha rotary joint, which has been operating in a degraded mode due to debris contamination. Garan installed a replacement of one of the joint’s 12 trundle bearing assemblies. Meanwhile, Fossum inspected a depression on the joint’s race ring and tried out several techniques for cleaning the debris.

Mission specialists Karen Nyberg and Akihiko Hoshide, KE5DNI, used the station’s robotic arm to remove the JPM from the shuttle’s payload bay and install it on Harmony, completing the task at 7:01 p.m.

On Wednesday, the crew will power up the newly installed JPM and open the hatches to begin outfitting the lab.