Family and friends of Expedition 51 Soyuz Commander Fyodor Yurchikhin of Roscosmos reacts as they see Yurchikhin enter the International Space Station during a live video feed of the Expedition 51 crew members a few hours after the Soyuz MS-04 spacecraft docked on Thursday, April 20, 2017 at Tsenki Conference Hall in Baikonur, Kazakhstan. Flight engineer Jack Fischer of NASA and Yurchikhin's arrival to the International Space Station comes the same day they launched from the Baikonur Cosmodrome in Kazakhstan. Photo Credit (NASA/Aubrey Gemignani)

Family of Expedition 51 Soyuz Commander Fyodor Yurchikhin of Roscosmos speak to him by phone a few hours after his Soyuz MS-04 spacecraft docked to the International Space Station (ISS) on Thursday, April 20, 2017 at Tsenki Conference Hall in Baikonur, Kazakhstan. Flight engineer Jack Fischer of NASA and Yurchikhin's arrival to the ISS comes the same day they launched from the Baikonur Cosmodrome in Kazakhstan. Photo Credit (NASA/Aubrey Gemignani)

Elizabeth Fischer, wife of Expedition 51 Flight Engineer Jack Fischer of NASA, speaks to him by phone a few hours after his Soyuz MS-04 spacecraft docked to the International Space Station (ISS) on Thursday, April 20, 2017 at Tsenki Conference Hall in Baikonur, Kazakhstan. Soyuz Commander Fyodor Yurchikhin of Roscosmos and Fischer's arrival to ISS comes the same day they launched from the Baikonur Cosmodrome in Kazakhstan. Photo Credit (NASA/Aubrey Gemignani)

A view of the projection screens from the Tsenki Conference Hall shows live video feed of the Expedition 51 crew members gathered together on the International Space Station a few hours after the Soyuz MS-04 spacecraft docked on Thursday, April 20, 2017 in Baikonur, Kazakhstan. Pictured are Expedition 51 crew members, Soyuz Commander Fyodor Yurchikhin of Roscosmos, bottom left, and Flight Engineer Jack Fischer of NASA, bottom right. Yurchikhin and Fischer's arrival to the International Space Station comes the same day they launched from the Baikonur Cosmodrome in Kazakhstan. Photo Credit (NASA/Aubrey Gemignani)

Elizabeth Fischer, wife of Expedition 51 Flight Engineer Jack Fischer of NASA, reacts as she sees Fischer enter the International Space Station during a live video feed of the Expedition 51 crew members a few hours after the Soyuz MS-04 spacecraft docked on Thursday, April 20, 2017 at Tsenki Conference Hall in Baikonur, Kazakhstan. Soyuz Commander Fyodor Yurchikhin of Roscosmos and Fischer's arrival to the International Space Station comes the same day they launched from the Baikonur Cosmodrome in Kazakhstan. Photo Credit (NASA/Aubrey Gemignani)