Mysterious incident caused NASA astronaut to lose the ability to speak

59-year-old astronaut Michael Fincke said on March 27 that an incident on the International Space Station (ISS) in January left him unable to talk and forced NASA to carry out the first medical evacuation of the station. The evacuation went smoothly, but until now doctors still don’t know why Fincke, who has flown into space four times, suddenly became unwell.

Fincke recalled that on January 7, after preparing for a spacewalk the next day, he had dinner and suddenly could not talk. He remembers not feeling any pain, but his teammates immediately requested help from the medical team on the ground. “It all happened completely unexpectedly, incredibly quickly. My teammates definitely realized I was in trouble. Within seconds, everyone quickly got involved,” Fincke told AP.

The incident lasted about 20 minutes, after which Fincke felt fine again. This astronaut said that the ultrasound machine on the space station is very useful when an incident occurs. He also added that he is currently healthy and has never experienced anything similar before or since.

Doctors have ruled out a heart attack, while Fincke also confirmed that he did not choke. However, all other possibilities are still being considered and could be related to the 549 days he spent in microgravity. NASA is reviewing the medical records of other astronauts to see if similar cases have occurred in space.

Fincke is part of the Crew-11 crew, flying to the ISS on SpaceX’s Crew Dragon Endeavor on August 1, 2025. The three remaining members of Crew-11 are astronauts Zena Cardman (NASA), Kimiya Yui (JAXA Japan Aerospace Exploration Agency) and Oleg Platonov (Russian space agency Roscosmos). The crew conducted research on human health and many other scientific studies on the ISS, and helped maintain the station’s operations in orbit.

According to Jared Isaacman, NASA Director, they completed almost all of the mission’s objectives before having to return a few weeks early due to medical problems. However, Fincke felt guilty and repeatedly apologized to those affected. He is also very optimistic and hopes that one day he can return to space.

Theo Live Sciencethe incident caused some experts to worry about health problems in space travel. In Fincke’s case, he could return quickly because the ISS station only flies in Earth orbit. However, on the Artemis 2 mission – NASA’s first human flight to the Moon in 54 years, scheduled for April – the crew will be far from Earth and much more difficult to evacuate urgently. To achieve the goal of establishing a permanent human presence on the Moon, NASA may need to ensure the best possible medical incident handling.