New Delhi, May 27 -- NASA astronaut Mike Fincke experienced a "medical emergency" in space earlier this year. He couldn't speak suddenly during the mission. The episode marked an early return of Crew-11, which he was part of. Months later, what he had suffered aboard the International Space Station remains a mystery.

In an interview with the Associated Press, astronaut Mike Fincke disclosed what had exactly happened on January 7, while he was still aboard the ISS.

Four-time space flier Mike Fincke told the outlet that he was eating dinner on January 7 after prepping for a spacewalk the next day when it happened.

He couldn't talk suddenly and remembered no pain, but his anxious crewmates jumped into action after seeing him in distress a...