Relief is on the way for the astronauts and cosmonaut aboard the international space station (ISS), who are gearing up for a crew exchange that will begin with the arrival of three new spaceflyers at the orbital laboratory April 8.

Russian cosmonauts Sergei Volkov and Oleg Kononenko, as well as South Korea’s first astronaut, So-yeon Yi, are slated to launch April 8 at 11:16 GMT aboard their Soyuz TMA-12 spacecraft from the Baikonur Cosmodrome, a Central Asian spaceport in Kazakhstan. Docking at the international space station is scheduled to take place April 10.

The crew swap marks the end of the six-month space station Expedition 16, led by NASA astronaut Peggy Whitson, commander of the mission, and the beginning
of Expedition 17, which Volkov will command.

“Expedition 16 and the upcoming Expedition 17 are truly an exciting time for the international space station program,” Kirk Shireman, NASA’s deputy station program manager, said in an April 2 mission briefing.

Volkov and Kononenko, both first-time spaceflyers, will relieve Whitson and flight engineer Yuri Malenchenko as the space station’s core crew and begin their own six-month mission in orbit. Flight engineer Garrett Reisman, a NASA astronaut currently aboard the ISS, will stay on as part of the Expedition 17 crew.

Yi will visit the orbital outpost for about nine days and return April 19 aboard the Soyuz TMA-11 spacecraft with Whitson and Malenchenko.

Originally assigned as backup for this mission, Yi was chosen to replace Seoul’s first choice, Ko San, after Moscow rejected him because he violated reading rules during training. Yi’s spaceflight is the result of a commercial agreement between the government of South Korea and Russia’s Federal Space Agency.

Her trip will make South Korea the world’s 35th country and Asia’s sixth to send an astronaut into space.

Expedition 16 was a packed tour aboard the ISS, with five spacewalks, three visiting shuttle missions and a host of scientific experiments taking place. The crew members helped install the hub-like Harmony connecting node, the European Columbus laboratory, a small Japanese storage module and a new Canadian robot on the space station.

“All of this was done very successfully, very safely, with very few issues along the way,” said Holly Ridings, Expedition 16 lead flight director. “It took a lot of diligence and focus from this amazing team.”

Whitson, the space station’s first female commander, is the first NASA astronaut to take part in two missions aboard the space station. Her first stay was as a flight engineer on Expedition 5 in 2002.

“A lot of the credit for how well it’s gone goes to commander Peggy Whitson,” Ridings said. “She really is the drive and the force behind all of those things happening on orbit on time and better than we could ever hope for.”

The rookie crew of Expedition 17 has one spacewalk scheduled. They also plan to help install a new large pressurized module for the Japanese Kibo laboratory, set to arrive in June, and get the station ready to host larger six-person crews starting in early 2009.

Though a rookie cosmonaut himself, Volkov has space in his blood. His father, Alexander Volkov, was also a cosmonaut, and visited Russia’s Mir space station.

The Expedition 17 crew’s arrival will come just five days after the successful docking of Europe’s Jules Verne unmanned cargo spacecraft.

“It’s a great time to be part of the international space station program,” Shireman said.