American flags, footprints, broken spacecraft, some plutonium, a couple of golf balls, a bible and a surprisingly large amount of human faeces. This is what humanity has left behind on the moon.

More than 50 years ago, US astronaut Neil Armstrong took that first “giant leap for mankind” onto the lunar surface, and over the following three years, 11 more astronauts across six crewed Apollo missions walked on the moon, collecting rocks that changed our understanding of how the Earth and the moon came to be (and even sneaking in a round or two of golf). But humans haven’t been back since.

Now another space race is kicking off, this time driven by not only geopolitical rivalry but a growing private industry (and some enthusiastic billionaires). NASA plans to land humans on the moon again in 2025, the first step to developing a permanent lunar base (with the aid of an Australian-made rover). China, Russia and other powers have similar ambitions. The moon is not only seen as a crucial launch pad for human missions to Mars and beyond – it’s rich in resources of its own, from rare metals to ice water. Consequently, it’s likely to be the first real frontier where space rules are made and tested.

Of course, scientists will tell you the moon is more important than any of that. Without its pull, life on Earth may not even be possible to begin with.

But, if you ask a guy named Dennis Hope in California, he owns the moon – having filed the paperwork at his local council 40 years ago – and all these big lofty plans to develop it will need his sign-off.

So, how are space lawyers unravelling who gets to take what from the moon? What will the rules up there look like? And why do we even have a moon?

What is the moon anyway?

Getting our moon was probably the best and the worst thing to ever happen to the Earth. The best because, without the stabilising gravity of our unusually large moon, we wouldn’t have the tides, and the Earth would wobble on its axis, swinging our climate from searing hot to freezing cold, perhaps too fast for life to adapt. And the worst because it really would have been the worst day in Earth’s history. It’s thought that our planet and another, roughly the size of Mars, collided in the early solar system some 4.5 billion years ago, soon (at least, cosmically speaking) after they had formed in the whirlpool of leftover gas and dust that forged our sun.

Earth would have been engulfed in fire but the other planet, named Theia for the mother of the moon goddess in Greek mythology, came off even worse, shattering apart in the smash. The moon is debris from the fallout, locked in Earth’s orbit.

This kind of ancient, cataclysmic “fender bender”, as astrophysicist Professor Jonti Horner at the University of Queensland calls it, is the leading explanation for why our moon is so big compared to other moons we’ve seen (almost a quarter the size of the Earth); and why it’s covered in a bright, glittery rock (the cooled remains of a magma ocean).

“Even with the naked eye, the moon sometimes seems close enough to reach out and touch,” says NASA scientist Professor Darby Dyar, who still remembers when the “mind-blowing” giant impact theory was first proposed. It is close, only 1.3 light seconds (or roughly 380,000 kilometres) from Earth, though each year it inches another four centimetres away. Dyar watched the Apollo astronauts “bouncing around [the moon] on grainy television broadcasts” as a kid and in 1979, as a 21-year-old PhD student, she found herself studying the lunar samples they brought home. “You can understand why my hands shook every time I had to handle them,” she says. “They still do!”

Those rocks changed our understanding of where the moon came from. But they threw up new mysteries too. Scientists thought that the moon must be a leftover chunk of Theia, likely its old core. But, while “it’s not made of cheese”, Horner says the moon is not made of the dense, heavy elements, such as iron, we’d expect to find in the core of an old, rocky planet like Theia either. Instead, it’s lighter, more like our Earth’s mantle and crust, with a tiny core. And when we study the moon’s chemical isotopes – that’s the signature of how rocks formed in different parts of the solar system – we find that the moon doesn’t look like a different alien world at all. It looks like Earth. “Every planet bears the scars of how they formed; they’re shaped by those final moments,” Horner explains. “But [chemically] it looks like the moon and Earth formed in the same place.”

A more recent study claims to have since found some discrepancies in moon isotopes, perhaps the first chemical fingerprints of Theia, though they are still small, according to earth scientist Qian Yuan at Arizona State University. One explanation is that the impact between the planets was so big they didn’t just collide, they fused, jumbling elements as seas of magma consumed their surface or perhaps forming a disc-like spread of material that coalesced back into the Earth and moon.

Another strange lead (“and most astronomy is detective work”, quips Horner) lies within the Earth itself. Scans have picked up two dense blobs, the size of continents, straddling the core like a pair of headphones. Scientists aren’t quite sure what they are but Yuan has outlined the strongest case yet that they could be leftover chunks of Theia, swallowed whole in the smash, and now buried beneath our feet in a kind of planetary graveyard.

In recent years, as technology improves, NASA has been releasing more moon rocks from deep freeze storage for study. “The fact that we’re interpreting the entire history of the Moon from a refrigerator-sized” crop of samples analysed so far has “undoubtedly been biasing our conclusions,” says Dyar, who is the lead on one of the new rock studies. NASA’s coming Artemis moon missions plan to bring back samples from different parts of it, including the deepest crater on its surface at the South Pole. “It’s so large we believe [the meteorite impact that made it] might have punctured through the moon’s crust and exposed part of the upper mantle,” Dyar says. “We think there are still liquid melts in the lunar interior, we know it’s not done cooling yet.”

Yuan hopes to match any such lunar samples to magma plumes from those two mysterious blobs that shot up through volcanoes on Earth. “We’d expect the moon’s crust and mantle to be different chemically, just like Earth’s layers are different,” he says. “So if we could compare the blobs to rocks from the moon’s mantle, not just its crust, we might have a match.”

What’s on the moon?

Our glittery moon is the brightest thing in the night sky – so bright that Horner usually hates when it’s out shining, bouncing back the sun’s light. “It blocks my view of other cool things I’m studying,” he laughs. But the moon offers its own unique window into our solar system. Because it has no climate or ocean, no weathering of its rocks, it keeps a pristine geological record. Scientists have devised ways of calculating what happened in our solar system’s ancient past by ageing the moon’s craters.

Horner himself dreams of setting up a telescope on the far side of the moon, the side that’s always dark to us, turned away. “It’s the quietest place in the solar system,” he says. The radio waves humans have been beaming out into space since the invention of broadcasting have travelled about one hundred light years away by now, but they don’t reach the far side of the moon.

That’s why China landing a spacecraft there for the first time in 2019, when the radio signal usually cuts out, was such a feat. “We are exploring more of the moon now,” Horner says. “Who knows what we’ll find next?”

Another reason the moon’s South Pole was chosen by NASA for its next landing? The ice.

One huge find in 2018 was NASA’s confirmation that ice-water, picked up for years by lunar missions (notably by India), was not just confined to cold, dark craters but spread across its sunlit face. That has made the idea of frequent trips to the moon and even lunar bases suddenly much more feasible, just as rockets are plummeting in price (thanks to lighter and more reusable designs by a new generation of space companies including Elon Musk’s SpaceX and Jeff Bezos’ Blue Origin).

Water is expensive to get into space – it’s heavy and every kilogram of weight means more rocket fuel to escape Earth’s powerful gravity. But water can also be split into its atomic parts: hydrogen and oxygen. Oxygen is obviously handy for life on an enclosed moon base, while hydrogen lets you make rocket fuel, says Horner.

So, another reason the moon’s South Pole was chosen by NASA for its next landing? The ice. “That crater is loaded with it,” says Horner. The European Space Agency has also unveiled plans to mine lunar ice and dust by 2025 – announced on the night of the super blood wolf moon of 2019. And China and Russia have their own joint plans to establish an International Lunar Research Station at the South Pole in the 2030s.

There have been some big dollar estimates for the value of lunar water mining. Silicon Valley space start-up Moon Express has called water “the oil of the solar system” and the moon “the eighth continent”. But Dyar stresses that water on the moon is “not a renewable resource”. The exact amount there is unclear. Some imagine the moon will instead become our “gas station” in space, Horner explains, an ideal base to refuel spacecraft as we mine asteroids rich in rare metals nearby or jet off on longer missions, including to Mars and Jupiter’s icy moons.

The moon has rare metals of its own too, the kind used in electronics and green energy tech but difficult and environmentally damaging to mine on Earth because there they are often deeper underground. “A lot of things that are not very rare in the cosmos are very rare in the crust of the Earth,” says Horner. “Some of these asteroids are the metal-rich cores of lost worlds.”

One asteroid, Psyche, which NASA plans to map in the coming months, is so rich in metals, including nickel and gold, that it’s said to be worth more than the global economy.

Dyar thinks the moon will not be mined so much as used as a staging post for other space industries. (As Horner notes, debate has already started on how to best preserve the historical and cultural value of the moon.)

But there’s something else on the moon some experts think could turn it into the next Persian Gulf: helium-3. Given the moon has virtually no atmosphere, particles from the sun have rained down on it for eons, including this rare isotope. Helium-3 is said to hold huge potential as an energy source through nuclear fusion, but it’s so rare on Earth that it has an astronomical price tag. (China, in particular, has been mapping estimated reserves on the moon).

Of course, it’s not all about stripping the moon for parts. There are hopes to set up solar panels on its surface to beam down huge quantities of renewable energy too. The moon also has very low gravity – just one-sixth that of the Earth’s. Everything is lighter, including heavy machinery (anyone touching down will need to spend a little time getting their “moon legs”), and so companies such as Blue Origin are already eyeing it as a new manufacturing hub.

So, who owns the moon?

Dennis Hope says he’s owned the moon for more than 40 years. He was struggling to get by and dreaming of owning real estate when he looked up at a full moon one night and thought, now, there’s a lot of property. Then he remembered learning about the Outer Space Treaty – that binding agreement from 1967 that lays the groundwork for governing peace in space. Ratified by 110 nations, the treaty rules out any national appropriation of the moon and other celestial bodies (or launching nuclear weapons from them, for that matter). But it doesn’t explicitly mention individuals owning land off-world.

So, Hope quickly filed a notice of ownership for the moon (and the other planets in the solar system) at his local council and set up the Lunar Embassy, a business selling small plots of lunar land for about $US25 (as well as acres on Mars, Jupiter and beyond). Today the company has sold land to more than 6.5 million people, says Hope’s son Chris Lamar, who now serves as CEO. “We’ve had celebrities, actors, former presidents buy.” And, though Hope wrote to the United Nations as well as the two major space powers at the time – the United States and the Soviet Union – asking if his claim was illegal, he has yet to hear back.

The company’s thinking is from old frontier law – many nations have laws allowing people to claim unoccupied land, and Lamar says space is the ultimate uncharted territory. “No one else was doing it and we got there first.”

Of course, according to the experts, Hope’s “loophole” is not the kind that would hold up in any court. The ’67 treaty, created during the Cold War space race, may have its gaps but it views the moon (and everything off-world) as a global commons, a bit like the high seas.“We all have a stake in it,” explains Emeritus Professor Steven Freeland from Western Sydney University and Bond University. “By all rights, it would have been great if they had also put up a UN flag” when the US made it first to the moon. “That US flag was an expression of national pride and prestige” but even then, America rushed to reassure the UN they hadn’t really claimed the moon with it.

Under the treaty, nations also cop responsibility for ensuring their citizens follow the spirit of international law. So that rules out private ownership. (Freeland’s missing out too – one of his classes bought him a Lunar Embassy plot “with all the title deeds,” he says. “It’s a novelty item.”)

Still, the treaty left room for interpretation too. In ’67, the US and Russia knew they were the big players, Freeland says, and set out some rules to work together – and to reassure the international community about their activities – but “why would they bind their own hands?”

In the late 1970s, as the potential for resource exploitation first came into focus, nations in the UN developed a new “Moon Agreement”. The moon and its natural resources were the common heritage of mankind, it said, but exploitation of those resources shouldn’t disrupt the moon’s environment and the benefits should be shared equitably (including among developing countries). An international regime would also be needed to manage lunar mining. Yet, when push came to shove, only 18 countries agreed to be bound by that agreement. US lobbyists argued it would create “a communistic approach to space”, says Freeland. (Australia ratified the agreement in ’86, under prime minister Bob Hawke, who also marshalled support to stop Antarctica from being mined through the Madrid Protocol of 1991).

Now, as travel and industry become increasingly more feasible on the moon, experts such as Freeland are finding a legal way forward. He co-chairs a UN working group charged with examining laws on space resource exploitation. Already, they have managed to get consensus among more than 100 nations, including Russia, the US and China, on how to proceed, even in the midst of Russia’s war on Ukraine. There’s momentum, but whether that leads to any new rules or treaty remains to be seen.

What’s clear, says Freeland, is that nations see big opportunities on the moon, including in science. A new crop of robotic missions is launching this year, from early Artemis test flights by NASA and SpaceX to a United Arab Emirates rover delivered by a Japanese lander.

Since Russia invaded Ukraine, the European Space Agency has called off planned collaborations with Russia’s Roscosmos agency on both the moon and Mars, though the ESA has previously had talks with China about its own planned “Moon Village” base and NASA recently flagged a European astronaut may land on the moon as part of strengthening US-European ties off-world. Russia, meanwhile, is looking to Beijing for moon collaboration, as China rises as a new force in space too, says Dr Malcolm Davis at the Australian Strategic Policy Institute. But, while NASA continues to work with Russia in space, it’s banned outright from collaborating with China.

Head of NASA Bill Nelson ruffled feathers earlier this year when he warned that China may be looking to claim the moon, even through a slow, creeping territory grab. “We must be very concerned that China is landing on the moon and saying, ‘It’s ours now and you stay out,’” he told a German newspaper. China immediately lashed the comment as a “lie”.

To Freeland, nothing could be worse than countries operating on the moon under different rules. “That’s a recipe for misunderstanding, miscalculations, and worse. We have to find a way, that even if they’re not co-operating with one another, they agree on and abide by the rules of the road.”

Who will profit from the moon?

If the first space race was about the race itself, about the prestige of being first, the new push to the moon is, largely, about money. This is the era of partnerships between government agencies and private companies – what people call “new space”, says Davis. “Although the moon is central to a lot of countries’ plans, it’s more about commercial gain now [as well as] national security and defence.”

In 2020, Morgan Stanley estimated that the global space industry could generate revenue of more than $1 trillion in 2040, up from $350 billion.

NASA is contracting companies to bring back moon rocks for small payments– something NASA could collect itself, but, which, experts say will help establish a precedent: a market to buy and sell things from the moon. And crucially, companies such as SpaceX and Blue Origin are helping supply cheaper, lighter rockets. Even NASA’s much-feted Artemis mission will use SpaceX rockets.

Lobbying by companies in the US has already led to the 2015 Space Act, which interpreted the Outer Space Treaty as allowing US citizens to own, use and sell resources they find in space. The idea is often compared to fishing in international waters – you might not own the water, but you can sell the fish. Luxembourg, Japan and the United Arab Emirates have followed suit with similar laws.

No one will spend money on space innovation otherwise, proponents argue, and too much regulation could kill the burgeoning industry, even though without it, says Davis, “it’s like the wild, wild West, it’s a free-for-all.”

Experts worry a “finders keepers” gold rush will trump the moon’s intended use “for the benefit of all”. Much of what is extracted in space is likely to stay off-world anyway to further interstellar expansion.

Laws now being developed to regulate deep sea mining in international waters could become models for the moon. A UN-created seabed authority requires nations or companies they sponsor to buy exploration licences beneath the waves. Space law expert Professor Dale Stephens at the University of Adelaide says you could imagine a similar system giving out “a temporary right to mine the moon … with responsibilities” and costs, “and then that money can be given to the UN” for humanitarian programs.

Of course, while developing the moon is no longer considered science-fiction, it won’t be easy either. When NASA’s Artemis mission lands the first woman and the first person of colour on the moon this decade, it will “inspire a new generation”, Horner says. But he thinks the main benefit of the new space race will be in spin-off technologies on Earth as engineers and scientists rush to tackle its challenges. One big one? Moon dust. Unlike on Earth, where dust is weathered down, moon rocks are sharp, made of fine glass, and pose serious risks to both human lungs and equipment. The dust even carries an electric charge.

And, without a protective atmosphere, moon bases will be exposed to space – from radiation to stray rocket crashes. (When it’s struck by a meteor, the moon rings like a bell. Sometimes it’s rocked by “moonquakes”.) Experts wonder if all the rocket exhaust on a moon suddenly booming with industry could start to build up – as others fret over space junk clogging its orbit. “And if we screw up space … we’ll all suffer because we all depend on space,” says Freeland. “The big [countries], who are the most dependent on space, have the most to lose – and therefore the greatest incentive to ensure this doesn’t happen.”

There’s talk of sustainable lunar development in a new code of conduct known as the Artemis Accords – these are agreements between NASA and some other space agencies (including Australia’s), as well as companies, about how they should behave in space and on the moon. But they are not binding international law, and Russia and China are among the nations who won’t sign, claiming the rules are designed to protect America’s edge in space. (They’re more likely to write their own versions.)

So, can we wreck the moon? Technically, we’ve already contaminated it. When the Apollo astronauts left bags of their poo behind to save weight on the trip home, they also dumped whole colonies of microscopic life. If something is still alive in it when humans return, we may have unintentionally proven the case that life can cross-pollinate between worlds, perhaps a crucial new twist in our quest to find aliens.

But, fortunately, Horner says, for all our technological advancement, we don’t have the means to knock the moon out of its orbit or interrupt Earth’s tides.

But could war break out on the moon?

When a group of Russian cosmonauts launch an ambush on a US moon base, high drama ensues in the TV series For All Mankind. The US astronaut is perplexed at first as the cosmonaut pulls a gun (very slowly, of course) and fires, the bullets cracking a window and sucking out air. The show is a reimagining of history (what if Russia had landed on the moon first?). Yet violent lunar scenarios are already being contemplated by real-life diplomats, politicians and space lawyers. Will the moon need its own police force? What happens if a major war breaks out back on Earth?

Unlike other international zones such as Antarctica, space is now a key war-fighting domain. In the 1960s, it was still “a very niche thing for defence forces”, says Davis. Now “everyone plugs into space, and we can’t fight without it.”

Destroying or jamming satellites, which relay military communications, launching cyberattacks, even taking over strategic points in space (including potentially on the moon). These could all come into play, though space is intended to be used peacefully. Low-orbit weapons around Earth already sit in military arsenals.

The Trump administration was mocked for creating a new arm of the US military, Space Force, in 2019, but many countries also have smaller space units within their existing forces, including Russia and China. And, although weapons testing is illegal on the moon, carrying a weapon is not. Russian cosmonauts, for example, have reportedly carried guns in their landing survival kits. (In 1965, two cosmonauts were stranded for days in the Siberian snow – bear country.)

If conflict broke out on Earth, Stephens says attacks on another country’s lunar missions could even become lawful acts of war. This very scenario has been raised during discussions with countries over the final draft of an upcoming academic guide to space law, The Woomera Manual, which Stephens is helping create. “If you’ve got human activity on the moon, you’re gonna need security,” he says. There is no guarantee humanity will suddenly be on its best behaviour. But would military astronauts conducting peaceful research get protected status or be targeted as soldiers during war, he wonders. “Are they like medics or chaplains? If one attacked the other would that be permitted? It’s still an open question.”

And, while astronauts pulling guns to contest a lunar claim may seem quaint, Davis says it shouldn’t be dismissed out of hand, even if he thinks most “warfare in space will be done by robots and uncrewed weapons systems, satellites as opposed to X-wing fighters in Star Wars”.

But, he adds, you could imagine a war off-world “20 years down the track when we do have a permanent presence on the moon, and we’ve got an American base and a Chinese base, and they’re both trying to compete over resources”.

Whether technology matches the warp-speed dreams of industry or not, Freeland agrees that our history on Earth sets a precedent worth taking seriously. Wars are “all about countries trying to claim territory or claim resources. I mean, look at what’s happening in Ukraine.”

Then there are citizens complicating the picture – a new crop of space tourists, asteroid miners, and the like expected to take to the skies down the line, likely with varying degrees of training.

Right now, astronauts are “envoys of mankind”, with an expectation they’ll be rescued if in trouble under international law. But “in a settlement on the moon, if you had a taikonaut, a cosmonaut, an Afronaut, [say] 20 people from 20 different nations all living together, all subject to their own national laws … what law applies?” Freeland muses. On the International Space Station, he says, such murkiness is sorted out ad hoc. But as more of us leave the Earth, we’ll need to rely on one another and establish a common code of conduct. “It’s a dangerous [environment]. I can’t open a window because I’ll kill everyone.”

Stephens says we are now entering a “new golden age” both for humans in space and the law. At the moment, “you’ve got the tension of some countries pushing, others pushing back. But then I think [there’ll be] a general recognition by everybody: let’s deal with it.”

Davis is less optimistic, saying that while the West may “go forward with all these new treaties and [regulations], patting ourselves on the back” the Chinese and the Russians might just do their own thing.

“If all we’re relying on is a hope that they have good intentions, well, hope is not a strategy.”

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