NASA STS-131 Status Report #16 10 p.m. CDT Monday, April 12, 2010

Mission Control Center, Houston, Texas

HOUSTON – Spacewalkers Rick Mastracchio and Clayton Anderson will begin the third and final spacewalk of the mission, finishing the installation of a new ammonia tank for the International Space Station’s cooling systems and continuing transfers equipment and supplies.

Mission Control played the song “Galileo” by the Indigo Girls as a wake-up for Mission Specialist Dottie Metcalf-Lindenburger and the rest of the baker’s dozen crew — Commander Alan Poindexter, Pilot James P. Dutton Jr. and Mission Specialists Stephanie Wilson, Naoko Yamazaki, Mastracchio and Anderson — at 9:21 p.m. CDT.

Mastracchio and Anderson spent the night in the Quest airlock, preparing their bodies for the lower pressure of the spacesuits, to protect against decompression sickness.

Robotic arm operators Stephanie Wilson, Dutton and Soichi Noguchi will activate Canadarm2, the station’s arm, and grapple the old ammonia tank that was removed earlier in the mission and stored on the station’s Mobile Base System. They’ll move the depleted tank into Discovery’s payload bay so that Mastracchio and Anderson can bolt it onto a logistics carrier for the ride home to Earth.

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