Spacewalkers Hard at Work on Third Trek

March 18, 2008

Mission Specialists Rick Linnehan and Robert L. Behnken are hard at work outside the orbiting complex formed by the docked International Space Station and space shuttle Endeavour. The two astronauts began the third spacewalk of the STS-123 mission at 6:51 p.m. EDT. The primary goal of this excursion is the outfitting of Dextre, the final element of the station’s Mobile Servicing System.

Mission Specialist Richard Linnehan checks out the spacesuits in the Quest airlock prior to the third spacewalk of the STS-123 mission.

With Mission Specialist Mike Foreman coordinating spacewalk activities from inside the orbiting complex, Linnehan and Behnken are installing a spare parts platform and tool handling assembly for Dextre. Among other tasks, they also are checking out and calibrating Dextre’s end effector and moving some spare parts.

In addition, the spacewalkers are tasked with installing the MISSE-6 materials experiment on the outside of the European Space Agency’s Columbus laboratory.

Space shuttle Endeavour Pilot Gregory H. Johnson and Expedition 16 Flight Engineer Garrett Reisman are operating the station’s robot arm during the spacewalk.

Behnken and Foreman are slated to begin the mission’s fourth spacewalk at 6:28 p.m. Thursday. The two will perform tasks that include a new procedure for repairing damaged heat-shielding tiles and change out of a circuit breaker on the station.

The spacewalk is the third of Endeavour's 12-day stay at the space station. On an earlier spacewalk, astronauts attached a storage compartment for a Japanese laboratory that is scheduled to by delivered by another space shuttle in May.