53-54 crewmembers pose for pictures in front of the Tsar Cannon as part of traditional pre-launch ceremonies.

Expedition 53-54 crewmembers Joe Acaba of NASA (left), Alexander Misurkin of Roscosmos (center) and Mark Vande Hei of NASA (right) pose for pictures in front of the Tsar Cannon in the Kremlin in Moscow Sept. 1 as part of traditional pre-launch ceremonies. They will launch Sept. 13 from the Baikonur Cosmodrome in Kazakhstan Sept. 13 on the Soyuz MS-06 spacecraft for a five and a half month mission on the International Space Station. Credit: NASA/Elizabeth Weissinger