Crews Prepare for Final STS-131 Spacewalk, Continue to Unload Leonardo

The Expedition 23 and STS-131 crews got back to work moving equipment and supplies to and from the International Space Station and preparing for Tuesday’s spacewalk, the third and last planned for the shuttle mission.

STS-131 Mission Specialists Rick Mastracchio and Clayton Anderson configured their tools in the Quest airlock. After a review of spacewalk procedures with other crew members, they are again spending the night in the airlock, its pressure reduced to 10.2 psi. That campout is aimed at reducing the nitrogen in their blood to avoid decompression sickness.

The spacewalk, replanned after difficulties bolting down an ammonia coolant tank on Sunday caused some rescheduling, is to begin at 3:11 a.m. EDT Tuesday and last 6½ hours. Activities include finishing the complicated change out of the large ammonia tank assembly, retrieving micrometeoroid shields from outside the airlock and retrieving a light-weight adapter plate assembly.

Mastracchio and Anderson completed the mission’s second spacewalk at 8:56 a.m. Sunday.

The shuttle and station crews continue to unload the Leonardo Multi-Purpose Logistics Module and transfer 17,000 pounds of science racks and other supplies into the station.