(Sen) - Russian cosmonaut Oleg Kononenko, NASA flight engineer Don Pettit and ESA's André Kuipers returned safely to Earth July 1 in a Soyuz TMA-03M spacecraft, ending 193 days in space and 191 days aboard the International Space Station. They landed in Kazakhstan 3:14 am CDT (8.14 GMT).
The return marks the end of Expedition 31 aboard the space station. The three returning astronauts had arrived at the space station on December 23 2011, spending over six months on the orbiting outpost.
During their expedition, the crew supported more than 200 scientific investigations in the only permanent microgravity laboratory. The studies ranged from investigations of the human cardiovascular and immune systems to fluid, flame and robotic research.
The returning trio have left the space station in the hands of Russian cosmonaut Gennady Padalka, NASA flight engineer Joe Acaba and Russian cosmonaut Sergei Revin. Before leaving, Oleg Kononenko handed over command of the station to Gennady Padalka. The Russian commander, along with Acaba and Revin have been on the space station since May 17 and will soon be joined by NASA astronaut Sunita Williams, Russian cosmonaut Yuri Malenchenko, and JAXA astronaut Aki Hoshide.
The Soyuz capsule in which the astronauts returned sits in a field in Kazakhstan. Credit: ESA/S Corvaja
Since the retirement of the Space Shuttle in 2011, the Russian Soyuz spacecraft is the only craft that is currently available to ferry astronauts to and from the space station. However, a number of private companies are developing craft with the aim of winning crew transportation contracts with NASA. Companies developing human spaceflight capabilities include SpaceX, which is modifying its Dragon spacecraft to carry astronauts. Dragon successfully demonstrated its ability to deliver cargo to the space station in May this year. Other commercial operations hoping to offer transport are ATK which is proposing 'Liberty'. Others include Boeing, Sierra Nevada Corporation and Blue Origin who are all hoping to demonstrate their crew ships for low Earth orbit missions.