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

A NASA astronaut has broken the record for the longest space mission in U.S. history.

Frank Rubio, 47, who has been aboard the International Space Station since September 2022 -- more than 355 days -- broke on Monday the previous record held by retired NASA astronaut Mark Vande Hei.

Rubio is not scheduled to return to Earth until Sept. 27, meaning he will be the first American and seventh person overall to spend more than a year in space.

He will have spent a total of 371 days orbiting Earth. The current record for most consecutive days spent in space overall belongs to Russian cosmonaut Valery Polyakov, who spent 437 days in space.

"Frank Rubio's journey in space embodies the essence of exploration. As he breaks records as the longest serving @NASA US astronaut in space, he also paves the way for future generations of astronauts. Your dedication is truly out of this world, Frank!" NASA Administrator Bill Nelson said in a statement posted on X, formerly known as Twitter.

In an interview with "Good Morning America" last month, prior to breaking the record, Rubio said he felt honored to hold the title and that he expected the record would be broken again in the future.

"I think this is really significant in the sense that it teaches us that the human body can endure, it can adapt and as we prepare to push back to the moon and then from then onward onto hopefully Mars and further on in the Solar System," he said. "I think it's really important that we learn just how the human body learns to adapt and how we can optimize that process so that we can improve our performance as we explore further and further out from Earth."

When Rubio originally lifted off last September -- riding aboard Russia's Soyuz MS-22 spacecraft with Russian cosmonauts Sergey Prokopyev and Dmitry Petelin -- his mission was only expected to last six months.

However, in December 2022, the day a scheduled spacewalk was planned, an external leak was detected from Soyuz MS-22, later determined to have been caused by a micro-meteorite impact.

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

During the "GMA" interview, Rubio said that a medical team examines astronauts within 10 minutes of their return to Earth, with many experiencing problems with their equilibrium at first, as well as walking and standing upright.

"I'm not sure how it will be for me," he said. "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."