Commander Gennady Padalka and Flight Engineer Michael R. Barratt of the 19th International Space Station crew are scheduled to launch in their Soyuz TMA-14 from the Baikonur Cosmodrome in Kazakhstan at 7:49 a.m. EDT Thursday to begin a six-month stay in space.

With Padalka, a colonel in the Russian Air Force, and Barratt is second-time spaceflight participant Charles Simonyi, flying under contract with the Russian Federal Space Agency. Simonyi previously flew to the station in April 2007 as a spaceflight participant with the Expedition 15 crew.

Simonyi will return to Earth with Expedition 18 crew members, Commander Mike Fincke and Flight Engineer Yury Lonchakov, in their Soyuz TMA-13 on April 7. Expedition 18 launched to the station Oct. 12.

Expedition 19 crew members will be welcomed by the Expedition 18 crew, including Japanese astronaut Koichi Wakata, after their docking to the orbiting laboratory, scheduled for Saturday

The Expedition 18 crew is returning to normal operations after 9 days, 20 hours and 10 minutes of docked operations with space shuttle Discovery. The STS-119 and Expedition 18 crews bid one another farewell and closed the hatches between the two spacecraft at 1:59 p.m. EDT. Discovery undocked from the International Space Station at 3:53 p.m.

STS-119 arrived at the station March 17, delivering the final pair of power-generating solar array wings and truss element to the station.

In addition, the STS-119 astronauts delivered Wakata, who replaced Sandra Magnus, now a mission specialist returning to Earth aboard Discovery.

The shuttle crew also performed three spacewalks while at the station.

Discovery is scheduled to land at Kennedy Space Center, Fla., Saturday.

All the crew members aboard space shuttle Discovery and the station gathered in the station's Harmony module Tuesday morning and spoke to U.S. President Barack Obama, members of Congress and students.

› View the shuttle and station crew members speaking with President Obama
› Listen to President Obama's call to the space station (19.2 Mb MP3)

For the latest news and information on the STS-119 mission, visit the main shuttle page. › Read more

Expedition 18 Commander Mike Fincke also provided a status to Mission Control on the spiders and butterflies that were delivered to the station on the STS-126 mission. Those experiment habitats were transferred to Discovery Monday, and will return to Earth when the shuttle lands Saturday.

› Listen to Mike Fincke's update to Mission Control (747 Kb MP3)

› Read more about Expedition 18
› View crew timelines