A Russian cosmonaut and a US astronaut returned to Earth on Thursday from the International Space Station (ISS) after 169 days in space, mission control in Moscow said.
"The crew of the Souyz TMA-16 craft is on Earth," it said in a statement, after Jeffrey Williams of the United States and Russia's Maxim Surayev touched down after five-and-a-half months together on the ISS.
At 1125 GMT, the spacecraft "made a safe landing in the designated area northeast of the town of Arkalyk" in the steppes of Kazakhstan, the mission control said.
"The cosmonauts are feeling well," it added.
"Working in frigid temperatures, Russian recovery teams were on hand at the landing site to help the crew exit the Soyuz vehicle and readjust to gravity," the US space agency NASA said in a statement.
NASA said that as members of the Expedition 21 and 22 crews, the two presided over the completion of the US segment of the space station.
The Russian-US duo had been high above Earth for 169 days, blasting off into space on September 30, 2009 and docking with the ISS on October 2, according Russia's mission control.
Until December 1, Surayev and Williams had worked as flight engineers in a crew that also included Belgian Frank De Winne, Canadian Robert Thirsk and Russian Roman Romanenko.
After Winne, Thirsk and Romanenko left, Williams assumed command of the ISS, which had been manned by just two people until three more crew members arrived on December 23.
The three current inhabitants -- Russia's Oleg Kotov, Soichi Noguchi of Japan and US astronaut Timothy Creamer -- will man the ISS until the arrival of a new spacecraft, the Soyuz TMA-18, whose launch is planned for April 2.
The ISS, which orbits 350 kilometres (220 miles) above Earth, is a sophisticated platform for scientific experiments, helping test the effects of long-term space travel on humans, a must for any trip to distant Mars.
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