An unprecedented space mission will be launching from NASA's Kennedy Space Center in Cape Canaveral, Florida, in the coming days. Dubbed Polaris Dawn, the first mission of its kind will use a SpaceX Falcon 9 rocket to launch a Crew Dragon capsule containing four private astronauts for a five-day orbit.

The mission is a follow-up of sorts to a 2021 private mission called Inspiration4 that was also backed by billionaire Jared Isaacman, the founder and chief executive of the data company Shift4. Polaris Dawn has been in the works for several years; at one point, there was talk of sending a crew to boost the life of the Hubble space telescope. 

This new mission isn't that. Instead, the crew will attempt the first spacewalk of private astronauts, using spacesuit technology developed by SpaceX. They will also test laser-based communications with satellite broadband provider Starlink as part of an effort to pave the way for travel to places including Mars. Starlink is a subsidiary of SpaceX, which is owned by Tesla CEO Elon Musk.

The risks aren't negligible: The crew will attempt to achieve the highest orbit of Earth ever recorded and will pass through heavy radiation and risk potentially significant damage from small space rocks and debris.

When will the Polaris Dawn mission begin?

After a series of launch delays, the Polaris Dawn mission now is scheduled to lift off no earlier than Monday, Sept. 9, according to the Kennedy Space Center and the Federal Aviation Administration.

The original launch date in the last week of August was scrubbed to allow for "a closer look at a ground-side helium leak on the Quick Disconnect umbilical," SpaceX said at the time on the X social network (formerly Twitter). A day later, the Polaris Dawn team stood down again "due to unfavorable weather in Dragon's splashdown area off the coast of Florida," the company said.

Isaacman posted on X that the launch team will assess conditions day by day. Potential launch dates in the first week of September have come and gone.

"Crew safety is absolutely paramount and this mission carries more risk than usual, as it will be the furthest humans have traveled from Earth since Apollo and the first commercial spacewalk!" Musk posted on X, which he owns. "If any concerns arise, the launch will be postponed until those concerns are addressed."

How can I watch and follow Polaris Dawn's mission?

In addition to news coverage, you can find updates on Polaris Dawn on the mission's website, X, Instagram and Flickr, where photos from the mission will be posted. 

Who'll be on the mission?

The crew comprises four members. They are:

Jared Isaacman, the Shift4 CEO who is said to be spending hundreds of million dollars on the mission, on which he will serve as mission commander. Isaacman was on the Inspiration4 mission in 2021 as well.

Sarah Gillis, SpaceX's senior operations engineer, who has trained NASA astronauts and who will serve as mission specialist for Polaris Dawn. Along with Isaacman, she will be one of the two crewmembers who performs the spacewalk.

Scott Poteet, who served as mission director of Inspiration4, is a former fighter jet pilot for the US Air Force. He will be doing communications and spacewalk assistance on the mission.

Anna Menon is a lead space operations engineer at SpaceX and will be in charge of the crew's health during Polaris Dawn.

What do they hope to accomplish on this mission?

In addition to the spacewalk, which Isaacman and Gillis will be the first private astronauts to perform, the mission will also test laser communications with Starlink and perform a series of biology and human endurance tests, according to the Polaris Dawn website.

The spacecraft is expected to travel to an orbit as far as 870 miles above the Earth, just past the altitude record of 853 miles set by the Gemini XI mission in 1966, according to The New York Times. For comparison, the International Space Station orbits at roughly 250 miles.

If successful, Polaris Dawn would be the first of three missions, the next two of which would use SpaceX's new Starship rocket. 

Correction, Aug. 28: An earlier version of this article incorrectly stated the name of Jared Isaacman's company. He is CEO of Shift4.