A billionaire entrepreneur, a retired military fighter pilot and two SpaceX employees are using the company’s new spacesuits and a redesigned spacecraft for the mission which launched on Tuesday morning from the Kennedy Space Center in Florida.
An attempt to launch last month was postponed hours before lift-off over a small helium leak in ground equipment on SpaceX’s launchpad.
The company fixed the leak, but its Falcon 9 was then grounded by US regulators over a booster recovery failure during an unrelated mission, further delaying the Polaris launch.
“Crew safety is absolutely paramount and this mission carries more risk than usual, as it will be the furthest humans have travelled from Earth since Apollo and the first commercial spacewalk!,” Elon Musk, SpaceX’s chief executive, wrote about the mission last month on his social media site X.
There have been roughly 270 spacewalks on the International Space Station (ISS) since its creation in 2000, and 16 by Chinese astronauts on Beijing’s Tiangong space station.
The SpaceX mission, called Polaris Dawn, will last about five days in an oval-shaped orbit that passes as close to Earth as 190km (118 miles) and as far as 1,400km (870 miles), the furthest any humans will have travelled since the end of the United States’s Apollo moon programme in 1972.