• The crew will reach altitudes higher than any human has traveled since NASA’s Apollo lunar program came to an end in the 1970s, climbing to a height of 870 miles above the surface.
  • The crew will spend five days in orbit testing space technology on behalf of SpaceX that could prove crucial as NASA and other space agencies set their sights on destinations like Mars.
  • On the sixth day of the mission, the SpaceX vehicle will reenter Earth's atmosphere and splash down at one of seven sites off the Florida coast.

A SpaceX Dragon carrying the four members of the Polaris Dawn crew is zooming into the upper reaches of Earth's orbit, where it should reaches heights higher than any human has traveled in decades.

Launching early Tuesday atop a Falcon 9 rocket, the spacecraft will ascend to 870 miles above Earth's surface before descending to a cruising orbit about 435 miles above Earth. On board the craft is an all-civilian crew under the command of billionaire entrepreneur Jared Isaacman.

Isaacman, who was also behind Inspiration4 – another historic commercial mission in 2021 that marked the first time an all-civilian crew went to space – helped to fund the mission along with SpaceX. Elon Musk's aerospace company also designed spacesuits specially for the Polaris Dawn crew.

The highly-anticipated launch followed about two weeks of delays as SpaceX awaited the ideal time to schedule a launch opportunity. During the ambitious mission, Isaacman and his crew hope to conduct the first-ever spacewalk made by anyone other than government astronauts while testing out SpaceX tech that could set the stage for future deep space exploration.

News about our planet, explained. Sign up for USA TODAY's Climate Point newsletter.

Polaris Dawn launches on SpaceX Dragon following 3 delays

After arriving three weeks ago at NASA's Kennedy Space Center in Florida, the Polaris Dawn crew boarded a SpaceX Dragon capsule for a 5:23 a.m. EDT liftoff Tuesday atop the Falcon 9.

Years in the making, the launch had previously been delayed three times – most recently due to poor weather conditions forecasted for the crew's return to Earth. SpaceX had been waiting for the past several days for weather conditions to improve off the Florida coast, where the crew will make a splashdown landing on the sixth day of their mission.

SpaceX had also previously delayed the launch for preflight checks and again when a helium leak was detected on a piece a equipment designed to detach from the rocket during takeoff.

The Federal Aviation Administration then briefly grounded the company's Falcon 9 following an uncrewed landing mishap. Fortunately for SpaceX – and the Polaris Dawn crew – federal regulators cleared the rocket to resume launches within a couple days.

Polaris Dawn crew to pass through Van Allen radiation belts

In the pre-dawn hours, spectators gathered all over the Florida coast to watch the daring mission get underway from launch Complex 39A.

After soaring skyward along a northeasterly trajectory, the rocket's first-stage booster was able to detach from the spacecraft within 10 minutes of launching, guide itself back to Earth and land as planned aboard a drone ship in the Atlantic Ocean. By 5:40 a.m., the Dragon spacecraft broke away from the Falcon 9's upper stage and began using its own thrusters to power on, SpaceX said on social media site X.

During the crew's first day in orbit, they will reach altitudes higher than any human has traveled since NASA’s Apollo lunar program came to an end in the 1970s. Climbing to a height of 870 miles above the surface – or more than three times higher than the International Space Station – will take the crew through the treacherous inner regions of Earth's Van Allen radiation belts.

The Van Allen belts pose one of the largest hazards to future spacefarers venturing deep into the cosmos. But for future expeditions to the moon and Mars to be possible, astronauts will have to be able to safely traverse them.

When the Polaris Dawn crew travels through the radiation belts, their SpaceX craft’s nose will be oriented to minimize the astronauts’ exposure to harmful radiation.

The crew will spend five days in orbit testing space technology on behalf of SpaceX that could prove crucial as NASA and other space agencies set their sights on destinations like Mars. On the sixth day of the mission, the SpaceX vehicle will reenter Earth's atmosphere and splash down at one of seven sites off the Florida coast.

Who are the crew of Polaris Dawn?

Isaacman, himself an experienced aviator, is the only member of the Polaris Dawn crew to have been to outer space before.

The billionaire founder of internet company Shift4 Payments will serve as mission commander of a crew that includes pilot Scott “Kidd” Poteet as well as mission specialists Sarah Gillis and Anna Menon, who is also the medical officer. Poteet, a retired United States Air Force lieutenant colonel who flew with the Thunderbirds, previously served as mission director for Inspiration4 – the world’s first all-civilian mission to space that introduced commercial space tourism to the world.

For Gillis and Menon, both lead space operations engineers at SpaceX, they have now become the first employees at the company to become part of a human spaceflight crew, according to SpaceX. Gillis also trained the Inspiration4 astronauts.

While in orbit, Menon, of Houston, plans to read a children's book she co-authored, "Kisses from Space" – inspired by her experience preparing for the Polaris Dawn mission – to her two young children.

A risky spacewalk and testing SpaceX tech

The crew will complete some 40 scientific experiments during the mission, many of which are to understand the human body's reaction to long spaceflights. They'll also test a new laser-based satellite communication system using Starlink.

But without a doubt, the highlight of the mission will be a bold spacewalk as the astronauts seek to become the first-ever private citizens to conduct the daring maneuver.

Taking place on the third day of the mission, the maneuver will only require Isaacman and Gillis to exit the Dragon. But doing so still exposes Poteet and Menon to considerable risk as well.

Until now, spacewalks have only ever been conducted by government astronauts. What's more, the maneuvers most often take place in craft with airlocks.

Because the Dragon does not have an airlock, the entire spacecraft will have to be depressurized when the hatch is opened, exposing the entire crew to the vacuum of space. For this reason, all four astronauts will be wearing Extra-Vehicular Activity (EVA) suits designed by SpaceX to receive oxygen through tethers.

"There's been a tremendous amount of preparation that’s gone into this by the SpaceX team," Menon told USA TODAY in a late-August phone interview from the Kennedy Space Center.

The purpose of the operation, which should take about two hours, is to test the suit's capabilities for SpaceX.

What's next for the Polaris Program?

Polaris Dawn is the first of three human spaceflights under the Polaris Program, all of which are intended to test SpaceX technologies needed to carry humans deep into the cosmos.

The second mission "will continue to expand the boundaries of future human spaceflight missions, in-space communications, and scientific research," according to the program's website. Additional details, including a launch date, have not yet been announced.

When the day comes that the third and final Polaris Program mission launches, it's intended to be the first human spaceflight on the SpaceX Starship rocket. The gargantuan rocket, which has so far only undergone uncrewed tests, will as early as 2026 be used to ferry NASA astronauts from lunar orbit to the moon's surface as part of the space agency's Artemis program.

Contributing: Brooke Edwards, Rick Neale, Florida Today

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at elagatta@gannett.com

Disclaimer: The copyright of this article belongs to the original author. Reposting this article is solely for the purpose of information dissemination and does not constitute any investment advice. If there is any infringement, please contact us immediately. We will make corrections or deletions as necessary. Thank you.