NASA Administrator Charles Bolden speaks during a news conference in Berlin on Monday. Bolden said no single country was indispensable to the International Space Station's success. Michael Sohn/AP hide caption

itoggle caption Michael Sohn/AP

From left: U.S. astronaut Steve Swanson, and Russian cosmonauts Alexander Skvortsov and Oleg Artemyev prior to the launch of their Soyuz-FG rocket Wednesday at the Baikonur Cosmodrome in Kazakhstan. Dmitry Lovetsky/AP hide caption

itoggle caption Dmitry Lovetsky/AP