ISS Crew Splashes Down on Earth After Medical Evacuation

American astronauts Mike Fincke and Zena Cardman, Russian cosmonaut Oleg Platonov and Japan's Kimiya Yui landed off the coast of San Diego about 12:41 a.m., marking the first-ever medical evacuation from the ISS.

The U.S. space agency has declined to disclose which crew member has the health problem or give details about the issue, but it has stressed the return is not an emergency situation.

The affected crewmember "was and continues to be in stable condition," NASA official Rob Navias said on Jan. 14.

The Crew-11 quartet arrived at the ISS in early August and had been scheduled to stay onboard the space station until they were rotated out in mid-February with the arrival of the next crew.

James Polk, NASA's chief health and medical officer, said "lingering risk" and a "lingering question as to what that diagnosis is" led to the decision to bring back the crew earlier than originally scheduled.

American astronaut Chris Williams and Russian cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev, who arrived at the station in November aboard a Russian Soyuz spacecraft, remained on the ISS. 

The Russian Roscosmos space agency operates alongside NASA on the outpost, and the two agencies take turns transporting a citizen of the other country to and from the orbiter, one of the few areas of bilateral cooperation that still endure between the United States and Russia.