The crew of the first fully private mission to the International Space Station was set on Sunday to leave the orbiting laboratory and head back to Earth.
The three businessmen and a former NASA astronaut had spent more than two weeks on the station on a history-making mission organized by startup company Axiom Space, Phys.org reports.
A SpaceX capsule was scheduled to undock from the ISS at 8:55 p.m. Eastern for the return trip, before landing in the ocean off the coast of Florida on Monday around 1 p.m.
The four men – three of whom paid tens of millions of dollars each for the rare chance to take part in the mission, and former astronaut Michael Lopez-Alegria, who holds dual U.S.-Spanish citizenship – were originally scheduled to spend only eight days on the space station.
But bad weather on Earth forced repeated delays in their return.
Private passengers Larry Connor, a U.S. citizen who heads a real estate company, Canadian businessman Mark Pathy, and Israeli former fighter pilot and entrepreneur Eytan Stibbe had blasted off from Florida on April 8, reaching the ISS a day later.
Once on board, they conducted a series of experiments in co-operation with Earth-bound research centres, including on cardiac health and cognitive performance in low gravity, according to a NASA blog.
Pathy in particular spent considerable time in the station’s famous observation cupola photographing the Earth from 400 kilometers overhead.
The mission was dubbed Ax-1 in a nod to Axiom Space, which served as a sort of space travel agency, paying SpaceX for providing two-way transportation and NASA for the use of the orbiting accommodations.
NASA has already given the green light, in principle, to a second mission: Ax-2.
The departure of the Ax-1 crew will leave seven people on the ISS: three from the U.S., a German, and three Russians. Monday’s sea landing of a manned Dragon capsule will be the fifth to date.
SpaceX, owned by entrepreneur Elon Musk, is regularly ferrying NASA astronauts to and from the space station.
Last year, SpaceX launched another entirely private mission, but it simply orbited the Earth for three days, not linking up with the ISS.