Crew members arrive before their planned Axiom Mission 2 at Kennedy Space Center
Commander Peggy Whitson, pilot John Shoffner, and mission specialists Ali Alqarni and Rayyanah Barnawi representing Saudi Arabia pose before the planned Axiom Mission 2 (Ax-2) launch to the International Space Station at Kennedy Space Center, Florida, U.S. Reuters

An all-private astronaut team of two Americans and two Saudis, including the first Arab woman ever sent into orbit, headed for splashdown off Florida's coast on Tuesday, capping an eight-day research mission aboard the International Space Station (ISS).

The SpaceX Crew Dragon vessel carrying the foursome, undocked from the ISS late on Tuesday morning to begin its 12-hour return flight.

If all goes as planned, the capsule will parachute into the Gulf of Mexico off Panama City, Florida, about 11 p.m. EDT (0300 GMT on Wednesday) following a fiery re-entry through Earth's atmosphere.

The return flight concludes the second space station mission organized, equipped and trained entirely at private expense by Axiom Space, a 7-year-old Houston-based company headed by NASA's former ISS program manager.

The Axiom 2 crew was led by retired NASA astronaut Peggy Whitson, 63, who holds the U.S. record for most time spent in orbit having logged 665 days in space during three long-duration missions to the ISS, including 10 spacewalks.

Ax-2's designated pilot was John Shoffner, 67, an aviator, race car driver and investor from Alaska.

Rounding out the crew as mission specialists were the first two astronauts from Saudi Arabia ever to fly aboard a private spacecraft - Ali Alqarni, 31, a fighter pilot for the Royal Saudi Air Force, and Rayyanah Barnawi, 34, a biomedical scientist in cancer stem-cell research.

Barnawi is the first woman from the Arab world ever launched into Earth orbit and the first Saudi woman to fly in space, an achievement that came barely five years after women in the Gulf kingdom gained the right to drive in June 2018.

In August 2022, Sara Sabry became the first Arab woman and the first Egyptian to fly to space on a brief suborbital ride operated by the Blue Origin astro-tourist venture of Jeff Bezos.

The ISS stay of Alqarni and Barnawi was also notable for overlapping with that of Sultan Alneyadi, an ISS Expedition-69 crew member from the United Arab Emirates, marking the first time three astronauts from the Arab world were aboard the space station together.

The Axiom 2 mission, which launched on May 21, is the latest in a series of space expeditions bankrolled by private investment capital and wealthy passengers rather than by taxpayer dollars as NASA seeks to expand commercial access to low-Earth orbit.

Axiom also has contracted with the U.S. space agency to build the first commercial addition to the orbiting laboratory.

California-based SpaceX, founded by Twitter owner and Tesla Inc electric carmaker CEO Elon Musk, supplied the Falcon 9 rocket and crew capsule that ferried Axiom's team to and from orbit and controlled the flight.

NASA furnished the launch site at its Kennedy Space Center in Cape Canaveral, Florida, and assumed responsibility for the Axiom crew during their stay aboard the space station, orbiting some 250 miles (400 km) above Earth.