Exploiting off-Earth resources could pave the way for human exploration of the Solar System
In July 2012, on Mauna Kea on Big Island, Hawaii, a small four-wheeled robot called Scarab trundled carefully round the slopes of the volcano, anxiously watched by an international team of engineers and space scientists. Under their direction, the little craft avoided rocks, fissures and gullies before beginning a task that has crucial implications for the exploitation of space – it started drilling into the volcanic crust to extract soil samples.
This test of robotic prospecting had been keenly anticipated. Scarab carried an instrument called RESOLVE – or Regolith and Environment Science and Oxygen and Lunar Volatile Extraction – developed by NASA and the Northern Centre for Advanced Technology (NORCAT) in Sudbury, Canada. Engineers think it could become the forerunner of an armada of automated craft that will one day exploit the Solar System’s mineral wealth and, in the process, transform life on Earth.
If we mine other bodies in space, we will no longer need to tear up our own planet’s surface and destroy its wild places to supply raw materials for our industries – we can ship them in from space instead. It’s an idea backed by entrepreneurs including film director and explorer James Cameron and Google chief executive Larry Page. The time to exploit the Solar System’s mineral riches has arrived, they argue. Not only will we save our planet from environmental destruction, but we’ll open the doors for manned travel to Mars and beyond.
First we have to find those riches, though – hence the interest in Scarab and RESOLVE. But the little robot is following in some big wheel tracks. NASA’s Curiosity rover – designed to analyse rocks on the surface of Mars in the search for clues about whether the Red Planet could have supported microbial life – cost more than US$1 billion to develop, is crammed with top-of-the-range equipment and is the size of a small car. Scarab is only a metre long and is designed to do just one task: finding water, cheaply.
“We want to prospect in space but will have to test our systems on Earth and show they work,” says Dale Boucher, a senior developer at NORCAT. “That is what RESOLVE will do. After that, we plan to build a robot prospector using the lessons we have learned with RESOLVE and hope to fly that to the Moon by 2020.”
THE MOON is a popular goal for space mining proposals. Its surface contains deposits of helium-3 – a potential fuel for nuclear fusion power plants – and rare earth elements – such as yttrium, dysprosium and lanthanum, which are crucial for the manufacture of solar cells, hybrid car batteries and LEDs (light-emitting diodes). But the Moon isn’t the only target under consideration. Other groups believe that asteroids, particularly those whose orbits bring them close to Earth, are a better option. Some contain vast reserves of nickel, iron, gold, silver and platinum.
Both destinations certainly have promise. The composition of the Moon’s crust is known, thanks to the work of NASA’s Apollo space program, and its riches are well understood. Similarly, meteorites, produced by asteroid collisions, tell us that there is great mineral wealth in asteroids. It’s accessing these sources that is the tricky part.
The Moon: 21st Century Lunar Exploration | NASA 360
“Consider the problem of landing on asteroids,” says Ian Crawford, of Birkbeck College, at the University of London, a planetary scientist and expert on extraterrestrial mining. “They have virtually no gravitational pull. You will need to find a way to tether yourself to an asteroid in order to mine it and as yet we have no idea how to do that. It will be like working on the space station but with a huge lump of rock hanging over you.” Likewise, setting up a lunar mining colony would require sending enormous amounts of equipment to the Moon, an enterprise that would dwarf the cost of the Apollo program.
Nevertheless, entrepreneurs are confident they can succeed. The Shackleton Energy Company, of Del Valle, Texas, which was set up in 2007, has already developed elaborate plans to prospect on the Moon. “We estimate that establishing a lunar mining outpost will cost about $20 billion and take about a decade to put in place,” says the company’s founder William Stone. “That may sound a lot but it is comparable to a North Sea oil production complex.”
Mining The Moon | Shackleton Energy
Planetary Resources – a newly formed company backed by X-Prize founder Peter Diamandis, along with Cameron and Page – is equally confident of commercialising space mining but with asteroids as their prime targets. “Thanks to exponentially growing technologies – in energy, artificial intelligence, electronics and other fields – small teams of scientists and engineers are now able to do what only governments could do in the past,” says Diamandis. “In our case, that means going into space and bringing the Solar System’s riches back to Earth.”
Planetary Resources | Company Overview
Given the current high cost of space flight, making money from extraterrestrial mining is, at the very least, problematic. Yet if it can be made profitable, it could well determine the future of humanity’s exploitation of space.
THE IDEA OF EXTRATERRESTRIAL MINING is far from new. Science fiction writer Arthur C. Clarke first proposed it in 1950, specifically referencing the Moon. “The Moon is a barren, airless, wasteland blasted by intolerable radiations,” he pointed out in his essay, ‘The Uses of the Moon’, published in 1966 in Voices from the Sky. “Yet a century from now it may be an asset more valuable than the wheat fields of Kansas or the oil wells of Oklahoma.” The crucial point about the Moon is that it requires 20 times less energy to escape from its surface than it does from the Earth’s, Clarke points out. Get your miners – humans or robots – up there and you’ve won half the battle.
It sounds straightforward, but there are stumbling blocks. The most important of these is getting round the exorbitant cost of setting up a lunar base in the first place and then keeping it supplied, Boucher says. “It costs $250,000 for each kilogram of cargo you take to the Moon. That’s a quarter of a million dollars to land a litre bottle of water there. You cannot run a colony at that cost. So if we are going to mine on the Moon the first thing we need to dig up is water.” Water is crucial to the entire idea of space mining, whether on the Moon or on asteroids. It’s needed not just to quench thirsts, but also to supply mining bases with fuel and oxygen – by using solar energy to break it into its constituent elements, hydrogen and oxygen.
RECENT MISSIONS have revealed deep craters near the lunar poles – where the searing rays of the Sun cannot reach – that appear to contain significant reserves of ice shed by comets and asteroids that collided with the Moon. In 2009, NASA’s LCROSS probe tracked a two-tonne Centaur rocket stage as it ploughed into the 100km-wide Cabeus crater near the Moon’s south pole – spectroscopic analysis of the debris thrown up showed it was rich in ice.
The discovery was a game-changer and suggests, Stone argues, that the Moon is now ripe for exploitation. “The first step will be to melt the ice and purify the water. Next, we electrolyse the water into gaseous hydrogen and oxygen, and then condense the gases into liquid hydrogen and liquid oxygen and also process them into hydrogen peroxide, all of which could be used as rocket fuels.”
LCROSS Finds Water on the Moon | MSNBC News Coverage
THIS TAKES US BACK to RESOLVE and its trials on Mauna Kea. Its prime task is to find not minerals, but moisture, in the volcano’s slopes. “We know there is water in the soil of Mauna Kea,” states Boucher. “The question is: can RESOLVE find it? If it can, we have a job for it to do – on the Moon.”
RESOLVE’s host, Scarab, looks fairly crude, with its tractor-like wheels and its power plant towed behind it. Soil samples are moved into a small oven and heated, and the gases produced are analysed for the presence of hydrogen, oxygen and other volatiles.
Stone envisages a series of Scarab-like probes being sent to the Moon to prospect for water in the loose surface soil – known as regolith – of places such as Shackleton crater near the lunar south pole. “Prospecting within the crater won’t be easy,” he admits. “It’s extremely cold – a steady -173°C – and perpetually dark, like the Antarctic winter, but worse because it’s constant. Our plan therefore calls for the development of a new generation of highly reliable, human-tended robotic machinery that would be built to withstand the harsh environment.”
The pioneers who will tend these robot miners will be housed in light, easily transported, inflatable buildings constructed from multilayer fabrics shielded with Kevlar and banded by steel skeletons, adds Stone. The minerals dug up would be sent to Earth using a mass driver – a launch track along which vehicles could be magnetically accelerated until they reached sufficient speed to escape from the Moon. Energy would be generated by solar plants.
This leaves us with the most important question: what will we mine when we actually get there? What will we dig up to generate the billions needed to support lunar mining colonies? Harrison Schmitt, an Apollo 17 astronaut and the only geologist to have walked on the Moon, is clear about the answer. Helium – and in particular, its rare isotope helium-3 – will make Moon mining worthwhile. “Returning to the Moon would be a worthwhile pursuit even if obtaining helium-3 were the only goal,” he says.
Schmitt, now based at the University of Wisconsin – Madison, argues that helium-3 is a perfect fuel for fusion reactors, which generate energy by combining the nuclei of elements at extremely high temperatures. Apollo mission samples, including material collected by Schmitt from Camelot crater in 1972, shows lunar soil contains up to 30 parts per billion of helium-3, atoms that have been wafted across space from the Sun over the past four billion years and that have accumulated on the Moon’s surface. (By contrast, Earth’s magnetic field has deflected helium-3 away from our planet.) Used in fusion reactors, the isotope has enormous potential, argues Schmitt. “Helium-3 could help free the United States – and the world – from dependence on fossil fuels,” he argues.
There are impediments to this plan, though. Even assuming a generous soil concentration of 30 parts per billion, you would have to dig a two-square-kilometre patch of ground to a depth of 2.7m to collect 100kg of helium, Schmitt admits. This would earn about US$141 million for the colony – a tidy sum – and would cost little to transport back to Earth. However, fusion reactors aren’t yet at a stage where they can provide homes and factories with electricity. Most scientists believe it will be another 50 years before fusion technology reaches that point. Only then might lunar helium-3 prove valuable.
THE MOON HAS OTHER RICHES, of course. In particular, there are rare earth elements that, as the name suggests, are found only in traces in rocks on Earth, but which are now crucial to the manufacture of many of modern luxuries. Colour TVs, iPods, fibre optic cables and lasers all need rare earths. The West currently gets 95% of these metals from China, but the Chinese government has recently made it clear it will soon switch to prioritising the supply of its own swelling electronics market.
The economics of off-planet mining are still shaky, say experts. Disused mines in the U.S. and Canada have ores containing rare earths at concentrations several thousand times higher than those found on the Moon. It would be far simpler and cheaper to reopen these.
That leaves us with asteroids. Could they provide minerals and metals more cheaply and easily than the Moon? In some ways, their potential is more obvious. A kilometre-wide, metal-rich asteroid could supply as much as US$8 trillion in minerals and metals, Crawford has calculated. Much of this would come in the form of nickel and iron, which are in fairly good supply on Earth. But, Crawford says, studies indicate that 0.1% of their ores are made up of platinum, gold, silver, iridium and other precious elements. These would have to be extracted and refined on site – so power plants and crew quarters would have to be set up, just as they would be on the Moon. Again, the availability of water will be crucial to operations; and again, supplies look promising. Surveys of asteroids suggest that many are simply burned-out comets rich in ice.
PINPOINTING ICY ASTEROIDS rich in metal ores will be the first task of engineers at Planetary Resources. In coming years, they plan to launch orbiting telescopes to search for candidate asteroids. Once one is selected, robot craft will be sent to mine for water and create fuelling depots of hydrogen and oxygen to supply further mining missions.
“The Solar System is full of resources and we are going to bring these back to humanity,” says Diamandis, who since his teenage years has dreamed of becoming an asteroid miner. Within a decade, that dream could come true, he believes. Chris Lewicki, Planetary Resources chief engineer, also is confident: “Three, four, five years out, depending on trajectory, is when we envision getting up close and personal with an asteroid.”
Asteroids typically range in size from just metres wide to nearly tens of kilometres long. It is the mid-to-high end of that range that offers most potential, argues Diamandis. Nor is there a shortage of asteroids that come close to Earth – there are probably 1,500 that pass near us, and at least 10% of them are likely have water and valuable minerals, he adds. As to the treasures that could be mined on them, Planetary Resources points to a range of precious metals, such as gold and platinum. Both are worth nearly US$1,600 an ounce, which certainly suggests a promising source of revenue.
THERE ARE DRAWBACKS. Critics point out that a forthcoming NASA mission to return just 60g of an asteroid to Earth will cost about US$1 billion. At that price, space miners will certainly not get rich on asteroid gold dust. Diamandis and his colleagues argue strenuously that in the near future they will cut mission costs drastically, enough to make their endeavours economically realistic. “It remains to be seen if they can do that,” says Crawford. “However, if they do succeed, they will face a second problem. If Earth starts getting supplies of cheap gold and platinum from space, their prices will drop and the whole economics of asteroid mining will crash.”
Most critics and observers doubt that either the Moon or the asteroids can be exploited purely as sources of minerals and metals for Earth. And, to be fair, most of its supporters would agree. Space mining is only a means to an end: the human colonisation of the Solar System. If we build fuel depots on the Moon or on an asteroid, and if we use the metals that we find there to build spaceships, we will avoid the extraordinarily expensive business of launching rockets from Earth, with its high gravity and thick atmosphere. That is the true justification of ventures such as Shackleton and Planetary Resources. As Stone says: “For the first time, access to space would be truly economical. At last, people would be able to begin new ventures, including space tourism, space-debris clean-up, satellite refuelling and interplanetary voyages.”
Deep Space Industries | Mining The Universe For The Future
Space mining should be seen as a starting point for beginning the manned exploration of the Solar System, for building observatories on the far side of the Moon, and for sending low-cost missions to the rest of Sun’s planets, say entrepreneurs like Diamandis and Stone. And yes, there will be some occasional benefits – a back-up supply of rare earth elements, for example. But the real point of lunar and asteroid mines will be the liberation of resources needed for the conquest of space.
There would also be one real bonus for those of us left on Earth, adds Crawford. “As mines dry up and we look for new sources of platinum or iridium or niobium, we may find that the only promising places left on Earth are protected habitats. Will we want to start strip mining in the Amazon or the Antarctic if the alternative is to dig up a dead piece of lunar soil or an asteroid? I think we will find the latter option a much more attractive one, so perhaps we should start finding ways to let it happen in the near future.”
via COSMOS (original article)
Journal of a Cosmic Anthropologist 