It’s a mission like no other. On Thursday morning, the SpaceX-operated Polaris Dawn will attempt something that’s never been done before: private civilians embarking on a spacewalk.

SpaceX’s newest adventure launched on Tuesday morning, sending four civilian astronauts on a five-day mission to a distance further from Earth than any crewed voyage since the Apollo programme in 1972.

Polaris Dawn is led by billionaire entrepreneur, Jared Isaacman, and crewed by two SpaceX employees and a former military pilot. After weeks of delays due to technical checks and weather, its astronauts are now weightless.

Until now, only government space programmes have commandeered spacewalks. Elon Musk’s SpaceX has new suits and big goals, and it wants to test them as fast as possible. It is now the only private company that delivers humans to live and work in space, and NASA, the space agency of the United States, relies on it.

Polaris Dawn is not a NASA mission, and it is not regulated by the US government. So when its astronauts exit their capsule and ‘walk’ in space, it will mark a massive first for the private industry that is starting to dominate realms beyond Earth.

And this raises a question: Is the US breaking a promise it made 50 years ago about how to operate in space?

A Cold War treaty faces a new test

“This is a mission which violates Article VI of the Outer Space Treaty,” Tomasso Sgobba, executive director of the Netherlands-based International Association for the Advancement of Space Safety told Al Jazeera in an interview. “It’s a well-known issue, which of course has a history.”

In 1967, deep in both the Cold War and the space race, the United Nations brought the Soviet Union, the US and other world powers to the table to sign a new agreement. The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies is now more commonly known as the Outer Space Treaty (OST).

It grew from agreements over sovereignty in Antarctica, and it is best remembered for committing the nations involved to keeping their powerful nuclear weapons on Earth, not hovering out in space. But the OST included another promise: that the exploration and use of outer space would, as long as its signatories agreed, be for the benefit of all humanity, and open to all nations. Space, the authors professed, would be a place to explore and learn from, not conquer.

However, the treaty also specified a role for private companies in space. Article VI reads, “The activities of non-governmental entities in outer space, including the moon and other celestial bodies, shall require authorization and continuing supervision by the appropriate State Party to the Treaty.”  In effect, the OST declared that home countries would be responsible for space activity from their soil, and would also be liable for them, should any accidents occur.

“The treaty is more valid today, and should be valid tomorrow,” said Ram Jakhu, former director of the Institute of Air and Space Law at McGill University. “If [Article VI] was not adopted, it would have been impossible to have this treaty.”

That is because the Soviet Union wanted only states to be involved in space activities, and the Americans wanted private companies. “So a compromise was made for private companies, subject to the permission, authorisation, supervision and responsibility of their respective states, and this is fundamental,” Jakhu explained.

Today, private companies are no longer just the parts suppliers for national space agencies, they are the explorers. Virgin Galactic and Blue Origin launch spaceflights for tourists. RocketLab, once a small startup, is planning a private science mission to the clouds of Venus. SpaceX is racing to land humans on Mars.

Does the US government still ‘supervise’ them?

“No,” said the Federal Aviation Agency by email to Al Jazeera. “Under federal law, the FAA is prohibited from issuing regulations for commercial human spaceflight occupant safety.”

This blunt reply is no accident. It is longstanding US policy. For 20 years, the US Congress has limited its aviation regulator’s oversight, placing a moratorium on making rules for private human space endeavours. The moratorium has been extended multiple times and will now expire in 2025.

Instead, the FAA only certifies the rocket and the spacecraft, ensuring, mostly, that they are safe for those back on Earth. “The FAA has no regulatory oversight for the activities of the Polaris Dawn mission,” the agency said.

The humans on board sign their informed consent. When they spacewalk, only SpaceX will look after them.

Al Jazeera contacted NASA, which confirmed that the agency has no involvement in the Polaris Dawn mission. (The mission’s Falcon 9 rocket launched from the Kennedy Space Center launchpad, which Elon Musk leases). SpaceX did not respond to questions sent by email.

What do spacewalks achieve?

Through the history of spacefaring, spacewalks have bridged the narrow gap between human necessity and human frailty.

When the Soviet Union and the US raced to space in the early 1960s, getting there was not enough; both countries wanted their astronauts to leave their capsules.

Within just a few months in 1965, both did. In March, Soviet astronaut Alexei Leonov, and in June, American astronaut Ed White, both floated, tethered above the Earth. But both faced immediate crises: Leonov’s suit expanded so much he had trouble re-entering his craft, and White’s door almost didn’t close after he did. An American astronaut who followed a year later nearly overheated.

Exposed in orbit, temperatures on surfaces are either very hot or very cold. Micrometeorites and space junk fly at speeds faster than bullets. Radiation penetrates the body more easily. Fabrics that are meant to hold back the fatal, freezing vacuum are inflexible and bulky. A space-sick astronaut could vomit, blocking their view or clogging their air. Just a decade ago, an Italian astronaut’s suit sprung a leak, and the small volume of water that collected in his helmet nearly drowned him before he could safely re-enter the International Space Station.

But spacewalks are essential: They have retrieved photo film from the Apollo missions near the moon, repaired Skylab, fixed the multibillion-dollar Hubble Space Telescope, and built the International Space Station. When it comes to the outsides of spacecraft, robots have never been able to do what humans can.

On Thursday, a new chapter in spacewalks will be written.

The crew of Polaris Dawn will vent the air from their capsule and open a door into the wide emptiness of outer space. Two of them will float out into it, tethered by umbilical cords.

To prepare for this, they will have spent almost two days exchanging the gasses in the cabin and within their bodies to prevent decompression sickness as they transition to their spacesuits.

After the short demonstration, they will close the door, and prepare to return to Earth – where a debate over the legality of the mission itself is dividing space analysts.

Who controls private missions?

Several experts say that the US is in no danger of violating the OST.

Jakhu said that when it comes to governments’ supervision of space activities, as obligated by the treaty, “there exist no internationally binding regulations that provide precise definition of this term and no international technical standards and procedure for effectively implementing this obligation”.

He said it was a question that deserved more attention in the coming years, but that each state “has discretion to define the term”.

That ambiguity – or room for interpretation – does not make the treaty outdated. Rather, in the new space race, he said, both powerful and emerging countries can and should rely on it, “to make sure private companies do not go out of control” in space.

Private companies may soon try to stake claim to objects in space for mining or construction. This could be allowed, within the sharing “use” principle in Article I of the treaty, similar to the rules at sea, or for the use of radio frequencies worldwide. But most importantly, these activities must be licensed by the state power back at home.

“It means the US government must take into consideration that it, too, should not do the things it does not like other countries doing. That’s why this treaty will [continue] to be successful,” Jakhu said.

In the new space race, he said, “private companies do not have allegiance to any particular country, and they could go to [the flag of] another [country].”

Tanja Masson, professor of international air and space law at Leiden University, says these agreements are not beneficial only for the countries.

“A bit of harmonisation is also in the interest of industry, who may operate from more than one country – they don’t want different rules to apply in the USA or in Luxembourg, for example.”

She agrees that SpaceX’s bold mission falls within Article I of the OST, which allows “free use” of space.

Asked how long the treaty will endure in today’s space race, “Forever!!,” she wrote in an email to Al Jazeera. “It’s sufficiently broad to accommodate new activities, and the principles should hold to preserve use and exploration for peaceful purposes. Even private actors agree the treaty must be kept and they can work with it.”

But Sgobba, who has decades of experience regulating space missions in Europe, disagrees.

He said SpaceX has some of the best safety experts in its ranks and is certain they have assessed all of this mission’s risks. But he said, “The lack of an independent oversight may have left somewhere an open issue which has not been identified.”

There are fire risks, and decompression sickness risks, in addition to the micrometeorites that may sling towards the crew undetected. He speculated that the European Space Agency or NASA may not have said yes to this kind of mission without a full redesign of the SpaceX Dragon capsule being used for Polaris Dawn.

Sgobba wants to see an international, independent space safety institute that would provide third-party reviews for space companies. Asked again by email whether the OST is seeing its first violations, he stuck to his initial assessment.

“I believe that article VI does not leave much room to interpretation,” he said. “The point remains that the large part of the Polaris Dawn mission is not currently subjected to authorisation and continuous supervision of any US government agency.”