US-Latino astronaut smashes old Nasa record for longest in-orbit mission

US astronaut Frank Rubio smashed the old record for the longest in-orbit mission by an American this week, spending over 355 days aboard the International Space Station (ISS), Science Alert reported.

"In some ways, it's been an incredible challenge. But in other ways, it's been an incredible blessing," Rubio said Wednesday from the ISS during a chat with Nasa that was broadcast live.

Rubio, who is a doctor by training and a helicopter pilot, expressed that he hopes to reach 365 days, saying: "I think that'll be a really good milestone for our nation to achieve."

Mark Vande's previous record of 355 days in space in 2022 has been smashed by Rubio while Russian cosmonaut Valeri Polyakov who holds the record with a duration of 437 days has not been touched.

Rubio will have spent 371 days in orbit by the time he returns to Earth on September 27.

Last year, Rubio and two cosmonauts stayed on a Russian Soyuz rocket to the ISS for six months. The rocket was intended to be an emergency escape vessel but suffered a leak due to a meteorite impact.

Russian space agency Roscosmos returned the damaged rocket and sent up another with no crew aboard the rocket.

Rubio and his two colleagues successfully completed their mission to replace the crew originally scheduled to travel to the ISS on the second rocket.

Rubio has had the opportunity to witness 28 different crews, consisting of individuals from various nationalities, come and go during his time in space.

"If I do the math right, that's almost five per cent of the humans that have ever been to space, which is pretty incredible," Rubio said Wednesday.

He described living and doing experiments in low Earth orbit.

"Once you're up here for a little bit, you really get focused on the work and sometimes you forget to appreciate the fact that you are floating around and that you have this amazing view down below you," Rubio said.

Rubio described the cramped quarters as a five-bedroom house, which was a challenge for him for a year.

The US record for most days in space over a lifetime is held by former astronaut Peggy Whitson, with 675 days.