Mike Fincke, the NASA astronaut with the fourth highest accumulated space time at 549 days, has retired, the agency announced on Wednesday, August 13, 2026.

During his 30-year tenure with NASA, Fincke served as commander, mission specialist, and flight engineer. He flew four missions and completed over 48 hours of spacewalks. Fincke recently piloted NASA’s SpaceX Crew-11 mission, which began in August 2025 but ended a month early in January 2026 after the crew evacuated the International Space Station (ISS) due to a medical issue involving Fincke.

Months before his retirement, Fincke became the first astronaut in NASA’s history to be medically evacuated from the ISS. He later clarified that the incident was not an emergency but required advanced medical imaging unavailable on the station.

Prior to his NASA career, Fincke served in the Air Force as a space systems engineer, flight test engineer, and flight test liaison, accumulating more than 2,000 flight hours across over 30 aircraft types.

In a statement announcing his retirement, Fincke said, “NASA gave me the extraordinary privilege of serving alongside remarkable people, flying and helping develop spacecraft, and contributing to the International Space Station from its earliest days through command in orbit.”

NASA Administrator Jared Isaacman praised Fincke, stating, “Few people have had the opportunity to shape as many chapters of NASA’s history as Mike Fincke.”