At the Baikonur Cosmodrome Museum in Kazakhstan Expedition 51 crewmember Jack Fischer of NASA displays a launch Key.

At the Baikonur Cosmodrome Museum in Kazakhstan, Expedition 51 crewmember Jack Fischer of NASA displays a “launch Key” during a tour of the facility April 14. The “launch key” is the device that triggers the engine ignition sequence at the launch pad for a Soyuz rocket launch. Fischer and Fyodor Yurchikhin of the Russian Federal Space Agency (Roscosmos) and Jack Fischer of NASA. Yurchikhin and Fischer will launch April 20 on the Soyuz MS-04 spacecraft for a four and a half month mission on the International Space Station. Credit: .NASA/Victor Zelentsov