Expedition 39 Trio Set to Depart Station

Three Expedition 39 crew members are wrapping up more than six months aboard the International Space Station as they get set for the journey back to Earth aboard a Soyuz spacecraft Tuesday.
Expedition 39 Commander Koichi Wakata of the Japan Aerospace Exploration Agency, Flight Engineer Rick Mastracchio of NASA and Soyuz Commander Mikhail Tyurin of Roscosmos, the Russian Federal Space Agency, will bid farewell to their station crewmates and close the hatches to their Soyuz TMA-11M spacecraft docked to the Rassvet module Tuesday afternoon. NASA Television coverage of the farewells and hatch closure begins at 3 p.m. EDT.
 When their Soyuz undocks at 6:36 p.m., it will mark the end of Expedition 39 and the start of Expedition 40 under the command of NASA astronaut Steve Swanson. Wakata, the first Japanese commander of the orbiting complex, passed the helm of the station over to Swanson during a change of command ceremony Monday afternoon.
 A deorbit burn at 9:04 p.m. will put the Soyuz on track for a parachute-assisted landing in the steppe of Kazakhstan southeast of Dzhezkazgan at 9:58 p.m. (7:58 a.m. Wednesday, Kazakh time). The landing will complete a journey of over 79 million statute miles and more than 3,000 orbits of the Earth for the trio since launching to the station from the Baikonur Cosmodrome in Kazakhstan back on Nov. 7.

Live NASA Television coverage of the undocking begins at 6:15 p.m. Coverage resumes at 8:45 p.m. for the deorbit burn and continues through the landing and post-landing activities.
Swanson and his crewmates, Alexander Skvortsov and Oleg Artemyev of Roscosmos, will operate the station as a three-person crew for two weeks until the arrival of three new crew members -- Reid Wiseman of NASA, Max Suraev of Roscosmos and Alexander Gerst of the European Space Agency. The trio of new flight engineers, who are wrapping up pre-flight activities in Star City, Russia, will fly to Baikonur on Thursday to begin the homestretch of preparations for their May 28 launch to the station.
Samples from the ongoing microbiome investigation will return on the Soyuz TMA-11M. The microbiome study looks at the impact of space travel on the immune system and on human microbiomes – microbes living in and on the human body at any given time. Samples from crew members’ bodies and the space station environment are taken periodically to monitor changes in the immune system and microbiomes. The results of this study may add to research on health impacts to people who live and work in extreme environments on Earth, and help with research on early disease detection, metabolic function and immune system deficiency.