Russian cosmonaut becomes 1st person to spend 1,000 cumulative days in space

A Russian cosmonaut became the first person to spend a cumulative 1,000 days in space, Russia's space agency Roscosmos announced Wednesday.

Oleg Kononenko, 59, reached the record while on his current mission aboard the International Space Station (ISS).

Kononenko's current mission to the ISS began Sept. 15, 2023, and is planned to end Sept. 23, 2024, which will bring in his total number of days spent in orbit to 1,110.

"Today at 00:00:20 Moscow time, Roscosmos state corporation cosmonaut Oleg Kononenko, who currently works at the International Space Station has booked a record of 1,000 days for the first time in the world in terms of total spaceflight duration," the Roscomos statement reads, according to state news agency TASS.

Kononenko cumulated the days in space over several missions. His first was Expedition 17 to the ISS, which launched in April 2008. In total, Kononenko has been on five separate missions to the ISS.

This is not the first record set by Kononenko. In February 2024, he surpassed the record of 878 days set by his colleague Gennady Padalka for longest amount of time in space.

"I fly into space to do what I love, not to set records. I've dreamt of and aspired to become a cosmonaut since I was a child," Kononenko told TASS at the time. "That interest -- the opportunity to fly into space, to live and work in orbit -- motivates me to continue flying."

Unlike the Roscosmos cosmonauts, NASA astronauts typically spend no longer than six months aboard the ISS before they're rotated out for a new crew. One notable exception was Frank Rubio, who spent 371 days in space before returning to Earth last September after his original six-month mission at the ISS was extended by an additional six months.

Experts have previously told ABC News that spending a prolonged period in space comes with many changes to human physiology and psychology and that astronauts are often extensively monitored upon their return after long missions.