Three rich businessmen returned from the International Space Station with their astronaut escort Monday, wrapping up a pricey trip that marked NASA's debut as a B&B host.
Flying back in a SpaceX capsule, they splashed down in the Atlantic off the Florida coast to close out a 17-day tour that cost them $US55 million apiece ($A77 millon) .
The trip was supposed to last a little over a week, but dicey weather kept the visitors in orbit almost twice as long as intended.
Before departing the space station Sunday night, the group thanked their seven hosts, including three NASA astronauts whose own mission is nearing an end.
It was the first time NASA opened its space hatches to tourists after shunning the practice perfected over the decades by Russia. Last fall, a Russian film crew flew up, followed by a Japanese fashion mogul and his assistant. In each case, an active-duty cosmonaut travelled with them.
The latest guests were accompanied by a former NASA astronaut now working for Axiom Space, the Houston company in charge of the flight, making it the first fully private trip to the space station.
After hosting longer than expected, NASA was itching to make room for the next crew. SpaceX will attempt to launch three NASA astronauts and one Italian to the space station as soon as Wednesday. They'll replace the three Americans and a German up there since November who will head back to Earth in their own SpaceX capsule.
The pace is blazingly fast by NASA standards. "It's absolutely exciting," said NASA flight director Zeb Scoville.
Axiom handled the logistics for the trip for its three paying customers: American real estate tycoon Larry Connor; Canadian private equity CEO Mark Pathy; and Israeli investor Eytan Stibbe of Tel Aviv. Their chaperone was Michael Lopez-Alegria, an Axiom vice president who flew to space four times while a NASA astronaut.
Lopez-Alegria said it was an "amazing adventure that we've had, even longer and more exciting than we thought."
Axiom teamed up with SpaceX for the journey that began with an April 8 liftoff from NASA's Kennedy Space Centre. It was SpaceX's second private flight, coming just months after a billionaire's orbital jaunt with contest winners.
While in space, the visitors did experiments and peered back at Earth.
"It's been eye-opening in so many ways," Pathy said, "that I think will have such a lasting impact on my life."
The experience was especially personal for Stibbe. He served as a fighter pilot under Ilan Ramon, Israel's first astronaut who died aboard space shuttle Columbia in 2003.
Stibbe flew copies of the surviving pages of Ramon's space diary, as well as artwork and music created by Ramon's children. He celebrated Passover with matzah bread he took up and gefilte fish offered by the station's Russians.
Axiom's second flight is set for early next year as the company looks ahead to having its own space station by 2030.