Can asteroid mining help further humankind’s space ambitions? Zoë Corbyn reports
A race is on to mine billions of dollars in precious resources from the solar system’s asteroids, fuelling our future among the stars, writes Zoë Corbyn
In an industrial park in San Jose, California, Grant Bonin is holding what looks like the end of a metal water bottle. It is the casing, he jokes, of his company’s “flying steam kettle”: a propulsion system for small spacecraft that uses super-hot water vapour, heated to 1,000C (1,832F), to produce thrust. The company has sold about 40 to date. “It comes right out of the hole,” explains Bonin, who is the chief technology officer of Deep Space Industries (DSI).
It is literally rocket science, but the ultimate aim of Bonin’s startup is even more audacious: mining asteroids. No private company has even got close to one. One of the main reasons asteroids will be mined in the future, so the thinking goes, is for the water locked in their clay deposits – and one of the chief uses of that water is likely to be as propellant for spacecraft. Probes and other spacecraft will be able to refuel in space either directly with water, or the hydrogen and oxygen that can be created from it, enabling them to zip around merrily anywhere they want with no end to their useful life.
But before the idea of a solar system dotted with gas stations is realised, what is needed are more spacecraft that can actually run on water, which is where selling flying steam kettles comes in.
The idea of mining asteroids is more popular than you might think. The oldest and biggest of the companies on the scene is Seattle-based Planetary Resources, established in 2009 by investors including Google cofounder Larry Page and Richard Branson. DSI was formed in 2013. Other smaller companies include Aten Engineering and the TransAstra Corporation, both also based in the US. In Britain, pursuing the idea is the Asteroid Mining Corporation (AMC). Established in 2016, it’s run by 23-year-old Mitch HunterScullion, who set up the company after his Liverpool Hope University dissertation on the topic.
As these companies see things, the inevitable next step for our civilisation is to expand into space. The Earth is too small for our increasing population, struggling over finite resources. To survive long term, they argue, we need to become a space-faring species. Human settlement won’t happen without the use of what is already out there, as transporting everything from Earth would be too expensive. Asteroids, says Bonin – with their negligible gravity making it easy to lift things off – are the “low-hanging fruit” of space resources.
Pickings are potentially getting richer as more asteroids are discovered close to Earth: about 18,000 and counting. Some of them, much closer than the ones in the asteroid belt between Mars and Jupiter, also pose a potential hazard to our planet. “The joke is that we’re threatened by giant piles of money,” says Bonin. The revolution in small low-cost satellites is opening up opportunities for these startups to prospect and survey them.
Some countries are offering regulatory and financial incentives to encourage the nascent industry. In July 2017, Luxembourg introduced legislation to allow companies with a physical presence in the country to keep any resources they mine from celestial bodies. Similar legislation was introduced in the US in 2015. Luxembourg also offers research and development assistance to space resource companies and invests directly in them through a fund of around €200m established for the purpose. DSI and Planetary Resources have both benefited. Development also takes people: master’s and doctoral degrees in space resources will begin this autumn at the Colorado School of Mines, which is starting the world’s first graduate programme in the subject. And while none of the companies have got near to an asteroid yet, Nasa and other space agencies have missions on the way that will demonstrate capabilities essential for asteroid mining.
Nasa’s Osiris-Rex spacecraft is scheduled to rendezvous with the Bennu asteroid – one of Earth’s most “potentially hazardous asteroids”, but also thought to be rich in water-bearing clay minerals – in December 2018. The spacecraft will flit around the half-kilometre diameter object making maps, before retrieving a 150g sample that will be returned to Earth, completing the $1bn project.
Before that, in mid-2018, Japan’s Aerospace Exploration Agency’s Hayabusa2 spacecraft is due to rendezvous with near-Earth asteroid Ryugu, also a samplereturn mission. It follows from the Hayabusa mission, which returned 1,500 grains of dust (about one milligram) from another near-Earth asteroid, Itokawa, in 2010 – the only sample of material to be brought back from an asteroid so far.
“Osiris-Rex is a proof of concept for any asteroid-mining activity,” says mission leader Dante Lauretta, a planetary scientist based at the University of Arizona. Chris Lewicki, CEO of Planetary Resources, draws a parallel with the way the US Geological Survey mapped the geology of America, helping early mining companies. “It is both public and private activities that move this forward,” he says.
To mine asteroids, DSI’s longterm vision is a swarm of small low-cost spacecraft that would go out to many near-Earth asteroids at once, harvest small amounts of raw material and aggregate them at a central depot that would be constructed at a gravitationally useful spot somewhere between the Earth and the moon.
“It is like honey bees going out to a lot of different flowers and flying that back to the hive,” says Bonin. The model circumvents the problem that the asteroids, with their heliocentric orbits, only fly past the Earth periodically and are therefore only accessible to mine for relatively short periods of time.
From the depot, the company would then sell whatever raw material made the most sense economically. That might be waterderived propellant (which would also fuel DSI’s “swarm”), but it also might be metals such as iron and nickel – for shaping into products by 3D printers – for construction in space. “To some extent we are agnostic about what the first market will be,” says Bonin. “We think it will be propellant for gas stations in space, but we wouldn’t want to bet.”
Planetary Resources is betting water will be the first market. One argument goes that there are already gas station customers in the solar system: rocket components that use liquid hydrogen and oxygen floating as space junk. If you could refuel them, you could do anything from servicing satellites to going to the surface of the moon, and that would be worth a lot of money, notes Lauretta, who is also on Planetary Resource’s science advisory board.
The UK’s AMC, meanwhile, imagines first mining platinum and similar metals – relatively abundant in asteroids – and sending them back to Earth. Going by the current value of platinum, trillions of dollars’ worth is out there. But, notes Lauretta, with a large supply prices would fall. “You would probably just crash the market and we would all have tons of platinum jewellery,” he says. Hunter-Scullion acknowledges the price would depreciate, but thinks it is possible to make a tidy profit first. Water, he says, would come next.
Of course, significant technical challenges abound, and they will probably cost billions to solve.
To go from recovering grams to kilograms, or tonnes, is a big technological jump and large infrastructure for refining and processing the asteroid ore will need to be developed. Even things like anchoring and holding on to an asteroid can be tricky. Their surfaces are lumpy and non-spherical and each has its own size, topography and rotation speed. Hayabusa only bought back any material because the spacecraft basically tumbled across the asteroid and some dust got into the equipment. “It is going to be a learning curve and at the moment we are at the bottom of it,” says Ian Crawford, a planetary science professor at the University of Birkbeck.
Whether space miners will be legally entitled to possess what they dig up also remains in question. The 1967 Outer Space Treaty (OST) – which governs international space activity – is silent on a private company harvesting space resources. It says nations can use but can’t appropriate either the moon or other celestial bodies. It puts the treaty and the national legislation in potential conflict, says Christopher Newman, a space law expert at the University of Northumbria. He predicts a dispute in the courts: “It is just a question of when.”
Hunter-Scullion, meanwhile, would like to see the British government introduce its own space-mining law, like the US and Luxembourg have done, giving private companies greater rights over asteroids.
The potential gets richer as more asteroids are discovered close to Earth – 18,000 and counting
An artist’s impression of the Nasa OSIRIS-REx spacecraft orbiting the asteroid Bennu. Nasa
A Japanese rocket launches in December 2014, carrying the Hayabusa2 probe on its way to the Ryugu asteroid. It is due to arrive later this summer.
The Asahi Shimbun/Getty
The Itokawa asteroid, left, is the only one from which material has been obtained so far – about one milligram of dust when the Hayabusa spacecraft bumped into it. Jaxa
Nasa’s OsirisRex, on display at the Kennedy Space Center, Florida, in 2016. It is currently on its way to the Bennu nearEarth asteroid. Reuters