By Irene Klotz and Dmitry Solovyov
CAPE CANAVERAL/ALMATY (Reuters) - An international space trio climbed into a Russian Soyuz spacecraft on Thursday and left the International Space Station after 199 full days in orbit to begin their delayed return to Earth, NASA Television showed.
Expedition 43 Commander Terry Virts of NASA, Samantha Cristoforetti of the European Space Agency and Russian cosmonaut Anton Shkaplerov gave a hearty hug to three crewmen remaining aboard the ISS before sealing themselves into the Soyuz TMA-15M spacecraft shortly after 0700 GMT (3 a.m. EDT).
Three hours later the Soyuz undocked from the Rassvet module at the $100 billion space outpost, aiming to land in central Kazakhstan at 1943 local time (1343 GMT).
"All Soyuz systems are operating in excellent fashion. No issues whatsoever at this stage," Russia's Mission Control near Moscow reported as the spacecraft floated away from the ISS.
The crew’s departure left Russian cosmonauts Gennady Padalka and Mikhail Kornienko and NASA astronaut Scott Kelly on their own until at least July 23, when cosmonaut Oleg Kononenko, NASA's Kjell Lindgren and Japan's Kimiya Yui are due to launch.
Kornienko and Kelly are about 2.5 months into a planned year-long stay on the station, a first for the 15-nation program. NASA is currently interested in accumulating medical data about long-term effects of microgravity in a space station as it lays the groundwork for eventual human missions to Mars.
Virts, 47, who had one previous space shuttle mission before flying to the space station last November, turned over command of the station to Padalka, 56.
Padalka, the first four-time ISS commander, will return to Earth in September after a cumulative total of some 878 days in orbit, more than any other person.
"No matter how many flights you have it’s always like ... a first flight," Padalka said during the ceremony, broadcast by NASA. "Hopefully, everything will be as scheduled and we’ll be looking forward to meeting the next crew."
The launch of the station’s next crew, which had been slated for late May, was postponed for two months due to questions about the Russian Soyuz rocket used to carry the passenger capsule into orbit.
A different version of the rocket failed to deliver a Progress cargo craft on April 28, and harmlessly fell into the Pacific Ocean in early May.
As a precaution, Russia delayed the launch of the new crew and kept the current team in orbit for an extra month to minimize the amount of time the station would be half-staffed.
The belated homecoming leaves Cristoforetti as the new record-holder for the single longest spaceflight by a woman, eclipsing NASA's Sunita William's 195-day flight in 2006-2007.
(Editing by Mark Heinrich)