Astronaut John McFall carries Paralympic flag at opening ceremony Aug. 28

Astronaut John McFall returned to the Paralympics today (Aug. 28) to carry the games' official flag in the opening ceremony in Paris.

McFall earned a bronze in the Paralympics Games in 2008, competing in the men's T42 100-meter race in Beijing. Today McFall has a different career, involving considerable medical expertise and participating in the European Space Agency as a reserve astronaut.

"I am truly honored to be standing here today, as a Paralympian and a member of the astronaut reserve with a physical disability," McFall said in a statement. "I like to think that my presence at this year's ceremony, in my new role at the European Space Agency, attests to and embodies the success, reach and legacy of the Paralympic movement."

McFall, along with French sailor and Paralympic champion Damien Seguin, each carried the Paralympic flag as they will be "representing the whole Paralympic community rather than a specific country", the statement added.

McFall was selected by ESA in 2022 and one of his major duties since has been finalizing the "Fly!" study. With other authors, he performed a range of tests to evaluate the capability of an astronaut with a lower leg prosthesis, like the ones he uses himself, for International Space Station (ISS) missions.

The study found no major issues for such a flight, but it does not stand as a guarantee that McFall will fly. Like other ESA reserve astronauts, he has done basic familiarization training and continues in his career (as a surgeon) while waiting a possible call-up for a future space mission.

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Speaking with Space.com earlier this month, McFall said he was glad to bring his passion for sport to the Paralympics -- even though he was nervous in the attempt as he prefers to compete against himself rather than others.

"I was that annoying kid who was in every sports team, but I didn't necessarily have aspirations of being an Olympic athlete. Following the loss of my my leg, I got back into running, and sport was a huge part of my life," McFall told Space.com in an exclusive interview Aug. 18.

As for the event itself, McFall's first emotion after crossing the finish line was relief as "I get incredible performance anxiety," he said. But the eight years of preparation helped him with other life endeavors, including becoming a physician and participating in the astronaut selection process: "What you put in — the effort [you put] in — you get reward back," McFall said. "It was a real life lesson for me."