Expedition 51 backup crewmembers practice rendezvous techniques on a laptop simulator as part of pre-launch activities.

At the Cosmonaut Hotel crew quarters in Baikonur, Kazakhstan, Expedition 51 backup crewmembers Sergey Ryazanskiy of the Russian Federal Space Agency (Roscosmos, center) and Randy Bresnik of NASA (right) practice rendezvous techniques on a laptop simulator April 13 as part of pre-launch activities. Ryazanskiy and Bresnik are serving as backups to Fyodor Yurchikhin of Roscosmos and Jack Fischer of NASA, who will liftoff April 20 from the Baikonur Cosmodrome on the Soyuz MS-04 spacecraft for a four and a half month mission on the International Space Station. NASA/Victor Zelentsov