Bill Ingalls / NASA via AFP - Getty Images
The Soyuz TMA-04M rocket launches from the Baikonur Cosmodrome in Kazakhstan on May 15, 2012.
Yuri Kochetkov / EPA
The Soyuz TMA-04M rocket blasts off from the Baikonur cosmodrome in Kazakhstan on Monday night.
Mikhail Metzel / AP
U.S. astronaut Joseph Acaba, left, Russian cosmonauts Gennady Padalka , center, and Sergei Revin, right, crew members of the mission to the International Space Station.
Bill Ingalls / AP
An Orthodox Christian priest blesses members of the media shortly after blessing the Soyuz rocket at the Baikonur Cosmodrome Launch pad Monday.
The Soyuz is slated to dock with the space station shortly after midnight ET Thursday. Once aboard, the three spacefliers will bring the orbiting complex back to its full complement of six residents. Their fellow Expedition 31 crew members — NASA's Don Pettit, Dutch astronaut Andre Kuipers and Russian cosmonaut Oleg Kononenko — have had the station to themselves since April 27.