A Russian Soyuz rocket streaked into the skies today over the Central Asian steppe, launching a U.S.-Russian-Brazilian crew on a mission to the international space station.

Russian Pavel Vinogradov and American Jeffrey Williams were to stay on board the station for about six months. Brazil’s first man in space, Marcos C. Pontes, will stay at the station for nine days before returning to Earth on April 9 with the station’s current crew of Russian Valery Tokarev and American Bill McArthur.

The Soyuz TMA 8 spacecraft is due to dock at the station early Saturday. Vinogradov, who is the commander of the crew, said they would carry out more than 65 scientific experiments during the mission, including some to test human reaction to prolonged space travel.

Vinogradov and Williams later were to be joined by European Space Agency astronaut Thomas Reiter, of Germany, when the space shuttle Discovery visits the space station in July. Once Reiter arrives, the station’s long-duration crew will be three in number for the first time since May 2003, following the Columbia disaster that February.