Expedition 31 crew members pose for a photo in the Unity node of the International Space Station.

Expedition 31 crew members pose for a photo in the Unity node of the International Space Station. Pictured on the front row are Russian cosmonaut Oleg Kononenko (center), commander; along with European Space Agency astronaut Andre Kuipers (right) and NASA astronaut Don Pettit, both flight engineers. Pictured on the back row (from the left) are NASA astronaut Joe Acaba, Russian cosmonauts Gennady Padalka and Sergei Revin, all flight engineers.