Who owns asteroids or the moon?

Plans to mine minerals on celestial bodies could violate many aspects of international space law

SHOULD asteroids rich in precious metals be regarded, in legal terms, like the fish in the sea? That is one approach the United Nations could take as it struggles to come to terms with mining plans announced by Planetary Resources, a start-up company based in Seattle.

In just under two years, Planetary Resources says it will launch the first of a series of space telescopes into low-Earth orbit in a bid to spot nearby asteroids of a size and mineral composition potentially worth mining. When a strong candidate is found, it plans to dispatch a robotic probe to assess the asteroid's precious metal content, with platinum a priority. If that is found, yet-to-be developed robots will be dispatched to mine it. If it is small enough, the asteroid could be brought into an Earth orbit first, to make the process easier.

Planetary Resources's plans seem well advanced and others are not far behind. And it's not just asteroids in these firms' sights. Moon Express, a start-up based in Las Vegas, is planning to prospect the moon for platinum and other metals deposited on its surface by meteorites.

It all sounds mind-bogglingly expensive and complicated, and it is. But those planning the operations have more earthly concerns to deal with, too. Mining asteroids or the moon appears to violate many of the tenets of international space law.

The most important of these is the UN's Outer Space Treaty of 1967, which in rather pompous language states that "the exploration and use of outer space shall be carried out for the benefit of all countries and shall be the province of all mankind".

It also specifically prohibits states from making territorial claims in space. "States cannot claim rights over an asteroid," says Joanne Wheeler, a lawyer at London legal practice CMS Cameron McKenna and a UK government adviser on the UN's Committee on the Peaceful Uses of Outer Space. "The Outer Space Treaty says the moon and celestial bodies such as asteroids are not subject to national appropriation. Whether that means no one owns the asteroids, or we all do under some common heritage, what's clear here is there is no state sovereignty over them."

What applies to sovereign states probably also applies to private companies. "It is not possible for Planetary Resources to say it owns all of an asteroid even if they are the first there," says Wheeler.

If the ownership of an asteroid is in question, who, then, has legal title to the ores extracted from it and sold back on Earth? Again, it is not clear, though Wheeler points out that there is already a legitimate market for space rocks in the form of meteorites. This probably puts Planetary Resources in the clear.

Eric Anderson, co-founder of Planetary Resources, doesn't see a problem: "Our analysis shows we have an unequivocal right to mine asteroids. Nothing in the Outer Space Treaty prevents that." He doesn't agree that asteroids, especially those in the 50 to 500-metre size range, are "celestial bodies". Meteorites are fallen asteroids, he says, and they are not regarded as celestial bodies.

Some even see the treaty as irrelevant to asteroid mining. "The Outer Space Treaty is a paper tiger with no teeth," says Michael Gold, a lawyer specialising in commercial spaceflight in Washington DC. "It's unenforceable and any state can pull out of it with a year's notice. I expect mining capability will trump the law in any situation."

Whichever interpretation you prefer, it is clear that there is no international regime explicitly governing asteroid mining. "Planetary Resources are in a rather grey zone," says Wheeler. "This is no legal certainty over whether they can do it or not."

She suggests that a future regime could be based on the law of the sea. "The fish in the high seas are not owned by anyone. You can 'mine' the high seas by taking fish out of them and you can sell them," she says. "Similarly, asteroids might not be owned by anyone but you might be able to mine the resources and then sell them on."

Mining the moon is also fraught with legal uncertainties. In principle it is governed by an international treaty informally called the Moon Agreement, which seeks to manage our satellite's natural resources. But the treaty is largely worthless because it has not been ratified by any of the spacefaring nations.

"The Moon Agreement recognises that mining of the moon is about to become feasible," says Wheeler. "But the US, China and Russia are not signatories, so it lacks teeth." The UN is encouraging members to sign, but the concern is that a fait accompli by a mining company could render the treaty moot.

Finally, what if space mining operations go wrong? If miners cause an asteroid that they have nudged nearer to Earth to plummet into the planet, who would be liable? This is covered by another UN treaty, the Space Liability Convention, which makes the nation that launches a spacecraft liable for damages. "This concept worked back when it was a clear-cut case of governments launching objects, but with many entrepreneurs now launching spacecraft it's getting much more difficult to apportion blame," says Wheeler. As a result, the US and Japan are investigating new liability mechanisms, she says.

The chances of Planetary Resources causing impacts are minimal, says Timothy Spahr, director of the asteroid-hunting Minor Planet Center at Harvard University. Orbital mechanics are well understood, he says, making asteroid trajectory calculations simple. "Hitting the Earth is a damn hard thing to do."

Like many astronomers, Spahr has an asteroid named after him. How would he feel about 2975 Spahr being captured and mined? "That's a tough question," he says. "You'd have to ask a lawyer."