ABC News September 21, 2023

Astronaut Frank Rubio marks 1 year in space after breaking US mission record

WATCH: NASA astronaut breaks record for longest trip to space by an American

After breaking the record earlier this month for the longest continuous amount of time spent in space by an American, NASA astronaut Frank Rubio on Thursday hit one year of orbiting Earth.

Rubio, 47, has been aboard the international Space Station with Russian cosmonauts Sergey Prokopyev and Dmitry Petelin since Sept. 21, 2022, in a mission that was only supposed to last six months when they traveled to the ISS aboard Russia's Soyuz MS-22 spacecraft.

However, in December 2022, the day a scheduled spacewalk was planned, an external leak was detected from the Russian spacecraft, later determined to have been caused by a micrometeorite impact.

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Because the spacecraft was unable to perform a crew return, the incident extended the three astronauts' stay for an additional six months. The Soyuz MS-22 returned to Earth uncrewed, and MS-23 was launched in February 2023 and docked at the ISS as a replacement for the crew's return later this month.

When Rubio and his two colleagues return to Earth on Sept. 27, landing in Kazakhstan, they will have spent 371 consecutive days in space. The current record for most consecutive days spent in space overall, with 437, belongs to Russian cosmonaut Valery Polyakov.

NASA via AP
This image provided by NASA shows astronaut Frank Rubio floating inside the cupola, the International Space Station’s "window to the world."

NASA congratulated Rubio in a post on the social media platform X on Thursday, writing, "Congratulations to NASA astronaut Frank Rubio for reaching one year on board the @Space_Station. On his first trip to space, Rubio has broken the record for the longest single spaceflight by an American astronaut in history."

Rubio broke the record on Sept. 11, surpassing the previous record of 355 consecutive days set by retired NASA astronaut Mark Vande Hei.

Over the year-long mission, Rubio and the other crew members have conducted numerous scientific experiments, including studying how bacteria adapt to spaceflight, using water-based and air-based techniques to grow tomatoes, and testing an expandable capsule for use in future space habitats.

During a media briefing on Tuesday, Rubio said if he had been asked beforehand to spend a full year in space, he would have likely said no.

"If they had asked me up front before training, because you do train for a year or two years for your mission, I probably would have declined," he said. "It would have hurt, but I would have declined and that's only because of family, things that were going on this past year."

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"Had I known that I would have had to miss those very important events, I just would have had to say, 'Thank you, but no thank you,'" Rubio continued, adding that he was excited to see his wife and four children.

In an interview with "Good Morning America" last month, prior to breaking the record, Rubio said he would undergo a medical examination upon his return to Earth because many astronauts struggle to walk and stand upright after spending prolonged time in space.

"I'm not sure how it will be for me," Rubio told 'GMA." "I'm preparing for the fact that it might be a challenge, that it might take a couple of days before I'm somewhat normal, but the reality is it's going to take anywhere from two to six months of really intense rehab to get back to my normal, and that's just part of the process."