AirshowExpedition 56 crewmembers pose for pictures in front of the Tsar Cannon as part of traditional pre-launch activities.

AirshowExpedition 56 crewmembers Serena Aunon-Chancellor of NASA (left), Sergey Prokopyev of Roscosmos (center) and Alexander Gerst of the European Space Agency (right) pose for pictures in front of the Tsar Cannon at the Kremlin in Moscow May 14 as part of traditional pre-launch activities. They will launch June 6 from the Baikonur Cosmodrome in Kazakhstan on the Soyuz MS-09 spacecraft for a six month mission on the International Space Station...NASA/Elizabeth Weissinger.