Astronauts from India, Poland, Hungary depart space station for return flight

Whitson, 65, and her three Axiom crewmates - Shubhanshu Shukla, 39, of India, Sławosz Uznański-Wiśniewski, 41, of Poland, and Tibor Kapu, 33, of Hungary - spent 18 days aboard the space station conducting dozens of research experiments in microgravity.

The mission stands as the fourth such flight since 2022 arranged by Axiom as the Houston-headquartered company builds on its business of putting astronauts sponsored by private companies and foreign governments into low-Earth orbit.

For India, Poland and Hungary, the launch marked the first human spaceflight in more than 40 years and the first mission ever to send astronauts from their government's respective space programs to the ISS.

If all goes as planned, the Dragon capsule will re-enter Earth's atmosphere at the end of a 22-hour return flight and parachute into the Pacific Ocean off the coast of California on Tuesday around 5:30 a.m. EDT (0930 GMT).

Dubbed "Grace" by its crew, the newly commissioned capsule flown for Axiom-4 was launched from NASA's Kennedy Space Center in Cape Canaveral in Florida on June 25, making its debut as the fifth vehicle in SpaceX's Crew Dragon fleet.

Axiom-4 also marks the 18th crewed spaceflight logged by SpaceX since 2020, when Musk's rocket company ushered in a new NASA era by providing American astronauts their first rides to space from U.S. soil since the end of the space shuttle program nine years earlier.

The Ax-4 multinational team was led by Whitson, who retired from NASA in 2018 after a pioneering career that included becoming the U.S. space agency's first female chief astronaut and the first woman to command an ISS expedition.

Now director of human spaceflight for Axiom, she had logged 675 days in space, a U.S. record, during three previous NASA missions and a fourth flight to space as commander of the Axiom-2 crew in 2023. Her latest mission commanding Axiom-4 will extend her record by about three more weeks.

Axiom, a 9-year-old venture co-founded by NASA's former ISS program manager, is one of a handful of companies developing a commercial space station of its own intended to eventually replace the ISS, which NASA expects to retire around 2030.