South Korean spaceflight participant So-Yeon YI jokes with Russian doctors in a helicopter after she and fellow crew members Expedition 16 Commander Peggy Whitson and Flight Engineer and Soyuz Commander Yuri Malenchenko landed their Soyuz TMA-11 capsule, Friday, April 19, 2008, in central Kazakhstan. Whitson and Malenchenko completed 192 days in space and Yi 11 days in orbit. Photo Credit: (NASA/Reuters/Pool)

Expedition 16 Commander Peggy Whitson, bottom, South Korean spaceflight participant So-yeon Yi and Flight Engineer and Soyuz Commander Yuri Malenchenko, top, walk down the airplane steps as they arrive at Chkalovsky Airport near Star City, Russia, Friday, April 19, 2008. Whitson, Malechenko and Yi landed their Soyuz TMA-11 spacecraft on April 19, 2008 in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Bill Ingalls)

Women in traditional Kazakh dress wait to welcome Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi at the Kustanay airport in Kazakhstan, Friday, April 19, 2008. Whitson, Malenchenko and Yi landed their Soyuz TMA-11 capule in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Bill Ingalls)

CHKALOVSKY, Russia -- Expedition 16 Commander Peggy Whitson waves to a crowd of well wishers from the top of the airplane steps as she arrives at Chkalovsky airport near Star City along with Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean So-yeon Yi. Whitson, Malechenko and Yi landed their Soyuz TMA-11 spacecraft on April 19, 2008 in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Bill Ingalls)

Expedition 16 Commander Peggy Whitson waves to a crowd of well-wishers from the top of the airplane steps as she arrives at Chkalovsky Airport near Star City, Russia along with Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi, Friday, April 19, 2008. Whitson, Malechenko and Yi landed their Soyuz TMA-11 spacecraft in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Bill Ingalls)

ISS016-E-036365 (17 April 2008) --- NASA astronaut Peggy Whitson (right), Expedition 16 commander; Russian Federal Space Agency cosmonaut Yuri Malenchenko, flight engineer; and South Korean spaceflight participant So-yeon Yi pose for a photo in the Harmony node of the International Space Station.

Russian ground crews walk around the Soyuz TMA-11 spacecraft after it landed carrying Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi, Friday, April 19, 2008, in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

A Russian search and rescue helicopter flies over the burning Kazakh steppe after Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi landed their Soyuz TMA-11 spacecraft, Friday, April 19, 2008, in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

The Soyuz TMA-11 capsule lays on its side on the Kazakh steppe, Friday, April 19, 2008. Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi landed their Soyuz TMA-11 spacecraft in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

Expedition 16 Commander Peggy Whitson is helped out of a helicopter after landing in northern Kazakhstan, Friday, April 19, 2008. Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi landed their Soyuz TMA-11 spacecraft in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

Rescue helicopters fly Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi to Kustanay, Kazakhstan shortly after their Soyuz TMA-11 spacecraft landed in central Kazakhstan, Friday, April 19, 2008. Whitson and Malenchenko completed 192 days in space and Yi spent 11 days in orbit. Photo Credit: (NASA/Reuters/Pool)

Expedition 16 Flight Engineer and Soyuz Commander Yuri Malenchenko sits in a helicopter after he and fellow crew members Expedition 16 Commander Peggy Whitson and South Korean spaceflight participant So-yeon Yi landed their Soyuz TMA-11 capsule, Friday, April 19, 2008, in central Kazakhstan. Whitson and Malenchenko completed 192 days in space and Yi 11 days in orbit. Photo Credit: (NASA/Reuters/Pool)

Expedition 16 Commander Peggy Whitson is helped out of a helicopter after landing in northern Kazakhstan, Friday, April 19, 2008. Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi landed their Soyuz TMA-11 spacecraft in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

A Russian ground crew member examines the over turned soil near the Soyuz TMA-11 spacecraft after it landed carrying Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi, Friday, April 19, 2008, in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

Russian Sokol flight suits of Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi are seen laying on the ground shortly after their Soyuz TMA-11 spacecraft landed in central Kazakhstan, Friday, April 19, 2008, to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Reuters/Pool)

JSC2008-E-032248 (7 April 2008) --- At their crew quarters in Baikonur, Kazakhstan, Expedition 17 Commander Sergei Volkov (center), Flight Engineer Oleg Kononenko (right) and South Korean spaceflight participant So-yeon Yi clasp hands for photographers on April 7, 2008, the eve of their launch to the International Space Station. Volkov, Kononenko and Yi are scheduled to launch to the station on the Soyuz TMA-12 spacecraft from the Baikonur Cosmodrome on April 8 and arrive at the ISS on April 10 to begin what will be six months in space for Volkov and Kononenko. Yi will be in space nine days on the complex, returning to Earth with two of the Expedition 16 crewmembers currently on the station. Photo Credit: NASA /Victor Zelentsov

JSC2008-E-032795 (8 April 2008) --- At the Baikonur Cosmodrome in Kazakhstan, Expedition 17 Commander Sergei Volkov (center), Flight Engineer Oleg Kononenko (right) and South Korean spaceflight participant So-yeon Yi bid farewell to well wishers April 8, 2008 prior to heading to the launch pad for their liftoff on the Soyuz TMA-12 spacecraft to the International Space Station. Volkov and Kononenko will spend six months on the station, while Yi will spend nine days on the complex under a commercial agreement between South Korea and the Russian Federal Space Agency. Photo Credit: NASA /Victor Zelentsov

JSC2008-E-032796 (8 April 2008) --- At the Baikonur Cosmodrome in Kazakhstan, the Soyuz TMA-12 spacecraft lifted off into a cloudless sky April 8, 2008 at 5:16 p.m. Baikonur time to carry Expedition 17 Commander Sergei Volkov, Flight Engineer Oleg Kononenko and South Korean spaceflight participant So-yeon Yi to the International Space Station and a docking on April 10. Volkov and Kononenko will spend six months on the station while Yi will spend nine days on the complex under a commercial agreement between South Korea and the Russian Federal Space Agency. Photo Credit: NASA /Victor Zelentsov

ISS016-E-035623 (10 April 2008) --- The Soyuz TMA-12 spacecraft approaches the International Space Station, carrying Russian Federal Space Agency cosmonauts Sergei Volkov, Expedition 17 commander; Oleg Kononenko, flight engineer; and South Korean spaceflight participant So-yeon Yi. Volkov and Kononenko will spend six months on the station, while Yi will return to Earth April 19 with two of the Expedition 16 crewmembers currently on the complex. Docking with the Pirs Docking Compartment occurred at 8:57 a.m. (EDT) on April 10, 2008.

International Space Station Program Manager Michael Suffredini watches as the first wave of helicopters leaves the Arkalyk airport in Kazakhstan in preparation for the Soyuz TMA-11 landing, Friday, April 19, 2008. The Soyuz TMA-11 spacecraft carrying Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spacelfight participant So-yeon Yi landed in central Kazakhstan to complete 192 days in space for Whitson and Malenchenko and 11 days in orbit for Yi. Photo Credit: (NASA/Bill Ingalls)

JSC2008-E-032794 (8 April 2008) --- At the Baikonur Cosmodrome in Kazakhstan, Expedition 17 Commander Sergei Volkov (center), Flight Engineer Oleg Kononenko (right) and South Korean spaceflight participant So-yeon Yi bid farewell to Anatoly Perminov, the head of the Russian Federal Space Agency on April 8, 2008, prior to heading to the launch pad for their liftoff on the Soyuz TMA-12 spacecraft to the International Space Station. Volkov and Kononenko will spend six months on the station, while Yi will spend nine days on the complex under a commercial agreement between South Korea and the Russian Federal Space Agency. Photo Credit: NASA /Victor Zelentsov

ISS016-E-035625 (10 April 2008) --- The Soyuz TMA-12 spacecraft approaches the International Space Station, carrying Russian Federal Space Agency cosmonauts Sergei Volkov, Expedition 17 commander; Oleg Kononenko, flight engineer; and South Korean spaceflight participant So-yeon Yi. Volkov and Kononenko will spend six months on the station, while Yi will return to Earth April 19 with two of the Expedition 16 crewmembers currently on the complex. Docking with the Pirs Docking Compartment occurred at 8:57 a.m. (EDT) on April 10, 2008.

ISS017-E-005014 (19 April 2008) --- Backdropped by the blackness of space and Earth's horizon, the Soyuz TMA-11 spacecraft departs from the International Space Station carrying NASA astronaut Peggy Whitson, Expedition 16 commander; Russian Federal Space Agency cosmonaut Yuri Malenchenko, flight engineer and Soyuz commander; and South Korean spaceflight participant So-yeon Yi. Undocking occurred at 1:06 a.m. (EDT) on April 19, 2008.

ISS017-E-005012 (19 April 2008) --- Backdropped by the blackness of space and Earth's horizon, the Soyuz TMA-11 spacecraft departs from the International Space Station carrying NASA astronaut Peggy Whitson, Expedition 16 commander; Russian Federal Space Agency cosmonaut Yuri Malenchenko, flight engineer and Soyuz commander; and South Korean spaceflight participant So-yeon Yi. Undocking occurred at 1:06 a.m. (EDT) on April 19, 2008.

ISS017-E-005007 (19 April 2008) --- Backdropped by the blackness of space, the Soyuz TMA-11 spacecraft departs from the International Space Station carrying NASA astronaut Peggy Whitson, Expedition 16 commander; Russian Federal Space Agency cosmonaut Yuri Malenchenko, flight engineer and Soyuz commander; and South Korean spaceflight participant So-yeon Yi. Undocking occurred at 1:06 a.m. (EDT) on April 19, 2008.

A Kazakh man herds cattle across the tarmac at the Arkalyk airport in Kazakhstan, Friday, April, 19, 2008. Arkalyk was used as one of the helicopter staging areas for the landing of the Soyuz TMA-11 spacecraft carrying Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi. The Soyuz made a ballistic landing, touching down more then 400 kilometers short of the intended target in central Kazakhstan. Photo Credit: (NASA/Bill Ingalls)

ISS017-E-005015 (19 April 2008) --- Backdropped by the blackness of space, the Soyuz TMA-11 spacecraft departs from the International Space Station carrying NASA astronaut Peggy Whitson, Expedition 16 commander; Russian Federal Space Agency cosmonaut Yuri Malenchenko, flight engineer and Soyuz commander; and South Korean spaceflight participant So-yeon Yi. Undocking occurred at 1:06 a.m. (EDT) on April 19, 2008.

A Russian Search and Rescue helicopter waits for refueling at the Arkalyk airport in Kazakhstan prior to taking off for the landing of the Soyuz TMA-11 spacecraft carrying Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi, Friday, April, 19, 2008. The Soyuz made a ballistic landing, touching down more then 400 kilometers short of the intended target in central Kazakhstan. Photo Credit: (NASA/Bill Ingalls)

Chief of the NASA Astronaut office, Steve Lindsey, left, and interpreter Paul Kharmats wait at the Arkalyk airport in Kazakhstan as Russian helicopters are refueled, Friday, April 19, 2008. Arkalyk was used as one of the helicopter staging areas for the landing of the Soyuz TMA-11 spacecraft carrying Expedition 16 Commander Peggy Whitson, Flight Engineer and Soyuz Commander Yuri Malenchenko and South Korean spaceflight participant So-yeon Yi. The Soyuz made a ballistic landing, touching down more then 400 kilometers short of the intended target in central Kazakhstan. Photo Credit: (NASA/Bill Ingalls)

ISS016-E-036441 (19 April 2008) --- The Expedition 16 crewmembers and spaceflight participant bid farewell to Expedition 17 crewmembers prior to boarding their Soyuz spacecraft for their trip back to Earth. Pictured on the right are Russian Federal Space Agency cosmonaut Yuri Malenchenko, Expedition 16 flight engineer, and NASA astronaut Peggy Whitson, Expedition 16 commander. Visible in the background is South Korean spaceflight participant So-yeon Yi. Russian Federal Space Agency cosmonauts Sergei Volkov (foreground) and Oleg Kononenko, Expedition 17 commander and flight engineer, respectively, are pictured at left.