Space Station Crew to Return to Earth Today
NASA astronaut Cady Coleman speaks during a change of command ceremony on May 22, 2011, one day before her planned return to Earth on a Soyuz spacecraft with Italian astronaut Paolo Nespoli (left) and Russian cosmonaut Dmitry Kondratyev. The three spaceflyers are ending their Expedition 27 mission to the International Space Station.
Credit: NASA TV

HOUSTON — It's landing day for two astronauts and a Russian cosmonaut on the International Space Station, with the three spaceflyers due to return to Earth tonight (May 23) after more than five months living and working in orbit.

Russian cosmonaut Dmitry Kondratyev, Expedition 27 commander, and astronauts Catherine (Cady) Coleman of NASA and Paolo Nespoli of Italy are poised to land their Russian-built Soyuz space capsule on the steppes of Kazakhstan in Central Asia at 10:26 p.m. EDT (0226 Tuesday GMT).  [Stunning Space Photos by Paolo Nespoli]

Kondratyev, Coleman and Nespoli will depart from the space station while the space shuttle Endeavour and its six-astronaut crew are docked at the orbiting laboratory. Endeavour launched on May 16 to fly one last space voyage before being retired. The shuttle's six-man crew is currently midway through a 16-day mission to help support station operations following the end of NASA's space shuttle program.

Yesterday, Kondratyev turned control of the space station over to fellow cosmonaut Andrey Borisenko, who will remain in command of Expedition 28 until his own return to Earth in September.

"I think we've done a lot of great science, and certainly I think the space station is in a really good state for the future," Coleman said during the change-of-command ceremony.

Mission's end in sight

Kondratyev, Coleman and Nespoli launched to the space station in December 2010 and have since spent just over five busy months on the orbiting outpost. After they leave orbit, and once shuttle Endeavour's crew heads home next week, the space station will be home to only three people: NASA astronaut Ron Garan and Russian cosmonauts Alexander Samokutyaev and Borisenko. [Inside and Out: The International Space Station]

Another three new station crewmembers are slated to launch to the orbiting outpost on June 7 to round out Expedition 28.

This morning, the space station crew will begin the work day at 7:31 a.m. EDT (1131 GMT). Undocking preparations will start at 9:26 a.m. EDT (1326 GMT).

Several hours later, the astronauts will participate in a farewell ceremony with their crewmates before the hatches are closed between the station and their Soyuz spacecraft at 2:30 p.m. EDT (1830 GMT).

Kondratyev, Coleman and Nespoli will undock from the station at 5:35 p.m. EDT (2135 GMT). After backing away to a distance of about 656 feet (200 meters), the spacecraft will pause for about 15 minutes, allowing Nespoli to position himself at a window in the Soyuz upper module to take video and photos of the space station and Endeavour.

The maneuver was universally approved by space station mission managers with NASA and Russia's Federal Space Agency. The unique images of Endeavour docked at the International Space Station will have some engineering applications, but will also be used to celebrate the legacy of the station and the space shuttle program.

After acquiring a series of images and video, Nespoli, Kondratyev and Coleman will continue with their journey home. The Soyuz will conduct a deorbit burn at 9:36 p.m. EDT (0136 GMT Tuesday) before the spacecraft re-enters Earth's atmosphere.

Kondratyev, Coleman and Nespoli are scheduled to land in Kazakhstan at 10:26 p.m. EDT (0226 GMT Tuesday).

Nespoli will be returning home after mourning the death of his mother from space. The Italian spaceflyer's 78-year-old mother, Maria Motta, died May 2 in her hometown just outside of Milan. Nespoli was notified immediately by the European Space Agency. Two days later, shortly after her funeral, Nespoli and his crewmates observed a minute's radio silence to honor Motta's memory, as the space station flew over Italy.

You can follow SPACE.com Staff Writer Denise Chow on Twitter @denisechow. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.