STAR CITY (Moscow Region), November 26 (RIA Novosti) - The main and backup crews for the next mission to the International Space Station (ISS) will begin on Thursday their final tests at a space training center near Moscow.

Russia's Soyuz-FG carrier rocket bearing the Soyuz TMA-17 spacecraft is scheduled to lift off from the Baikonur space center in Kazakhstan on December 21.

"A two-day final exams session must confirm the readiness of cosmonauts and astronauts for the space flight planned for the second half of December 2009," a Russian official at the training center at Star City told reporters on Wednesday.

The main TMA-17 crew comprises Russian cosmonaut Oleg Kotov, U.S. astronaut Timothy Creamer, and Japanese astronaut Soichi Noguchi.

Noguchi will be the second Japanese astronaut to fly on a Soyuz, after Toyohiro Akiyama.

The backup crew comprises Russian cosmonaut Anton Shkaplerov, U.S. astronaut Douglas H. Wheelock, and Japanese astronaut Satoshi Furukawa.

The main crew will take their tests on Thursday on a ground simulator of the Russian segment of the ISS, while the backup crew will be tested on a Soyuz spacecraft simulator.

On Friday, the crews will trade places, and a special commission will announce the final crew composition on Thursday based on the results of the tests.

TMA-17 will be the 104th flight of a Soyuz spacecraft since 1967. The spacecraft will most likely remain docked with the space station for the remainder of the Expedition 22 mission to serve as an emergency escape vehicle.