Mastracchio during EVA 2

ISS023-E-021510 (11 April 2010) --- NASA astronaut Rick Mastracchio, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Mastracchio and astronaut Clayton Anderson (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.