A billionaire entrepreneur, a retired military fighter pilot and two SpaceX employees have been orbiting Earth aboard Crew Dragon since Tuesdays pre-dawn launch from Florida of the Polaris Dawn mission.
It is the Elon Musk-led companys latest and riskiest bid to push the boundaries of commercial spaceflight.
Live streaming of the event is set to begin at 8.55am GMT (10.55am SAST), SpaceX said on Thursday, with two astronauts venturing outside Crew Dragon while two stay inside.
The capsule, at an altitude of 700km, will be completely depressurised, and the whole crew will rely on their slim, SpaceX-developed spacesuits for oxygen.
Jared Isaacman, 41, a pilot and the billionaire founder of electronic payments company Shift4, is bankrolling the Polaris mission, as he did his Inspiration4 flight with SpaceX in 2021. He has declined to say how much he is paying for the missions, but they are likely to cost hundreds of millions of dollars, based on Crew Dragons price of roughly US$55-million a seat for other flights.
