Astronaut Mike Fincke and his Crew 11 colleagues are returning early from the International Space Station due to a medical issue affecting an unidentified crew member, though all are reported as stable and well cared for.

The crew, including Zena Cardman, Kimiya Yui, and Oleg Platonov, will undock Wednesday and splash down in the Pacific Thursday morning, followed by medical evaluations onshore.

This marks the first time in NASA history a crew has cut its mission short for a medical reason, though the issue is not considered an emergency.

Fincke praised NASA’s careful planning and support for the crew, noting the decision was made calmly to ensure proper medical care, CBS News has reported.

Command of the station will transfer to cosmonaut Sergey Kud-Sverchkov, leaving him and his Soyuz MS-28 crewmates alone until Crew 12 arrives in mid-February.