Commander Bill McArthur, flight engineer and Brazil's first astronaut, Marcos Pontes, departed the orbital outpost shortly before 4:30 p.m. EDT and were expected to touch down in a remote region of Kazakhstan three hours later.
"Congratulations on a very successfully led expedition and a very safe landing," astronaut Julie Payette, speaking from NASA's Mission Control Center in Houston, radioed to McArthur as he and his crewmates prepared to enter the Soyuz.
At the time of McArthur's launch six months ago, there was no plan in place for his ride home. Russia's original agreement to supply Soyuz rides for American crewmembers ended with the return of McArthur's predecessor in October 2005.
But U.S. legislators agreed to lift a ban on the purchase by NASA of space services and hardware from Russia. The ban was enacted on concerns that Russia was helping Iran develop nuclear weapons and missile delivery systems.
Though weapons proliferation issues remain a concern, U.S. occupancy of thewould have come to an end if NASA had not been granted a waiver to buy Russian space services.
NASA's own transport to the space station, the three-vehicle shuttle fleet, has only flown one marred mission since the 2003 Columbia disaster, which claimed the lives of seven astronauts.
Additional work on the shuttles' fuel tanks, which was determined to be the cause of the accident, continues and NASA hopes to return the shuttle fleet fully to flight in July.
During a televised farewell ceremony, McArthur, a former Army officer and test pilot, noted that he and Tokarev were the only two people to be living off of Earth and that "it has been an extraordinary privilege for us to represent humankind."
McArthur and Tokarev were the 12th crew to live aboard the space station. They were replaced by commander Pavel Vinogradov and flight engineer Jeffrey Williams.
Guest astronaut Pontes, who flew to the station with the incoming crew, spent eight days on the station conducting experiments, photographing Earth and being interviewed.
Recovery teams were in position in Kazakhstan to assist the returning crew.