U.S. astronaut Christina Hammock Koch, a member of the International Space Station (ISS) expedition, attends her final exam at the Gagarin Cosmonauts’ Training Center in Star City outside Moscow, Russia, Wednesday, Feb. 20, 2019. Koch and Nick Hague along with Russian cosmonaut Alexey Ovchinin are preparing for the launch onboard the Soyuz MS-12 spacecraft from the Russian-leased Kazakh Baikonur cosmodrome on March 14, 2019.