Three spaceflyers aboard a Russian Soyuz spacecraft are due to arrive at the International Space Station later today (Dec. 17) to join the crew.
The Soyuz TMA-20 spacecraft carrying NASA astronaut Catherine Coleman, Russian cosmonaut Dmitry Kondratyev and European astronaut Paolo Nespoli is scheduled to dock at the space station at 3:12 p.m. EST (2012 GMT). [Graphic: Inside and Out: The International Space Station]
The trio launched from the Baikonur Cosmodrome in Kazakhstan on Wednesday (Dec. 15), before spending two days chasing down the station and entering its orbit.
Coleman, Kondratyev and Nespoli will join the space station's existing Expedition 26 crew ? station commander Scott Kelly of NASA and flight engineers Alexander Kaleri and Oleg Skripochka of Russia, who have been living at the station since early October.
The incoming crew is poised to begin a five-month stay in space, during which Coleman, Kondratyev and Nespoli will conduct a variety of research experiments and educational outreach. They will also oversee the arrival of two unmanned cargo supply vessels ? the European Automated Transfer Vehicle (ATV) and the Japanese H-II Transfer Vehicle (HTV).
Additionally, the station crew will play host to two upcoming space shuttle visits in the new year. The STS-133 flight of the shuttle Discovery is targeted to launch in February 2011, and the subsequent STS-134 flight of Endeavour is pegged for April.
Both flights will be the last missions for the respective orbiters before NASA retires its space shuttle fleet next year. After the shuttle program's retirement, the Russian Soyuz spacecraft will be the only link for humans to fly to space until an American commercial vehicle is available.
During their months-long stay onboard the station, Coleman and Nespoli will perform duties as flight engineers. Kondratyev will begin his mission as a flight engineer as well, but will take over as the space station commander for Expedition 27.
The six-person Expedition 26 crew will spend about three months together before Kelly hands over command of the station to Kondratyev. Kelly, Kaleri and Skripochka are set to return to Earth in mid-March, while Coleman, Kondratyev and Nespoli will remain on the station until May.
- Graphic: Inside and Out: The International Space Station
- Gallery: Space Windows on the World
- Is the International Space Station Worth $100 Billion?
You can follow SPACE.com Staff Writer Denise Chow on Twitter @denisechow.