STS131-S-015 (5 April 2010) --- Space shuttle Discovery and its seven-member STS-131 crew head toward Earth orbit and rendezvous with the International Space Station. Liftoff was at 6:21 a.m. (EDT) on April 5, 2010, from launch pad 39A at NASA's Kennedy Space Center. Onboard are NASA astronauts Alan Poindexter, commander; James P. Dutton Jr., pilot; Rick Mastracchio, Dorothy Metcalf-Lindenburger, Stephanie Wilson and Clayton Anderson; along with Japan Aerospace Exploration Agency (JAXA) astronaut Naoko Yamazaki, all mission specialists. The crew will deliver the multi-purpose logistics module Leonardo, filled with supplies, a new crew sleeping quarters and science racks that will be transferred to the International Space Station's laboratories. The crew also will switch out a gyroscope on the station’s truss structure, install a spare ammonia storage tank and retrieve a Japanese experiment from the station’s exterior. STS-131 is the 33rd shuttle mission to the station and the 131st shuttle mission overall.