USA astronaut Jack Fischer, above, and Russian cosmonaut Fyodor.
A Soyuz manned spacecraft scheduled to take off tomorrow to the International Space Station is the first in the batch to get a name, Argo, Roscosmos has announced.
Nasa's Jack Fischer and Russia's Fyodor Yurchikhin lifted off from the Russia-leased launch facility in Kazakhstan at 1.13pm local time on Thursday, reaching orbit about nine minutes later, a moment illustrated when a small white stuffed dog hanging from a string in the capsule began to float.
A Soyuz-FG carrier rocket is scheduled to launch from the Baikonur Cosmodrome at 10:13 a.m. Moscow time on April 20 to deliver the Soyuz MS-04 spacecraft to the International Space Station.
Mr Yurchikhin, 58, has made four space flights before but his NASA rookie crewmate is on his maiden voyage, and fears figuring out how to use the zero-gravity toilets aboard the ISS may be his biggest challenge.
"It's all about suction, it's really hard", Mr Fischer told NASA in an interview before the launch from Kazakhstan's Baikonur cosmodrome.
Yurchikhin and Fischer are set to complete a five-month mission at the station.
"You can't just train for that on the ground, so I approach my space-toilet activities with respect, preparation and a healthy dose of sheer terror". Commander Whitson, 57, in the midst of her third long-duration mission, is due on Monday to beat the 534-day record for cumulative time spent in space by a US astronaut.
Fischer and Yurchikhin join a crew commanded by NASA's Peggy Whitson.
The previous three flights of the Soyuz MS spacecraft were held under a two-day scheme as they were carried out in the testing mode.