Two Russians on September 20 set a record for the longest continuous stay on the International Space Station (ISS), according to Russian space agency Roskosmos.
Roskosmos said Oleg Kononenko and Nikolai Chub broke the old record of 370 days, 21 hours and 22 minutes, which was set in September 2023 by Russians Sergei Prokopiev and Dmitry Petelin and American Francisco Rubio.
Chub and Kononenko will add several days to their total before their scheduled return to Earth on September 23.
Kononenko, 59, holds other space duration records, including the most cumulative time in space -- 1,110 days over the course of five missions by the time he lands later this month in Kazakhstan.
In comparison, the NASA astronaut with the longest cumulative days in space, Peggy Whitson, ranks eighth internationally. Whitson has been in space for a total of 675 days cumulatively in three long missions and one short term mission.
Two American astronauts, Butch Wilmore and Suni Williams, who are currently on the ISS, have inadvertently been aboard the space station for much of the Russians' record-setting stay.
After NASA and Boeing identified helium leaks and issues with the reaction control thrusters in the astronauts’ Starliner space capsule, a decision was made to send the capsule back without Wilmore and Williams and keep them at the ISS for their own safety.
NASA said the return of the Starliner without a crew allowed it and its manufacturer, Boeing, to continue gathering testing data while at the same time not creating risk for its crew.
NASA has considered that the astronauts' extended stay means they will not be on Earth for the U.S. presidential election in November. The pair of astronauts told reporters during a press conference on September 13 that they will still have a chance to vote in the election and will use satellites to beam their votes down to Earth.
The two U.S. astronauts are set to return to Earth in February.