Expedition 31 Preflight

Expedition 31 NASA flight engineer Joe Acaba, right, flight engineer Sergei Revin and Soyuz Commander Gennady Padalka enter a mockup Soyuz TMA spacecraft in order to perform final qualification tests in preparation for flight, Tuesday, April 24, 2012 at the Gagarin Cosmonaut Training Center in Star City, Russia. Acaba, Revin and Padalka are set to launch to the International Space Station May 15 from the Baikonur Cosmodrome in Kazakhstan. Photo Credit: (NASA/Carla Cioffi)