Expedition 31 Preflight

Expedition 31 NASA flight engineer Joe Acaba signs for his Soyuz vehicle simulation test card before senior officials at the Gagarin Cosmonaut Training Center, Tuesday, April 24, 2012 in Star City, Russia, while his fellow crew members Soyuz Commander Gennady Padalka, left, and flight engineer Sergei Revin look on. Acaba, Padalka and Revin are set to launch to the International Space Station May 15 from the Baikonur Cosmodrome in Kazakhstan. Photo Credit: (NASA/Carla Cioffi)