Among Avatar’s many striking images are aerial views of RDA’s great unobtanium mine on Pandora. It looks like a lunar landscape cut out of the green, across which giant machines crawl. The sheer scale of all this is brought home to us in Jake’s first scenes on Pandora, when, fresh off the Valkyrie shuttle from orbit, he is tiny beside dump trucks, their wheels taller than a standing human—but in other shots we see how the trucks themselves are dwarfed beside the tremendous excavators in the pit.
The size of an RDA excavator, a DD40 Heavy Duty Class Wheel Loader, is staggering. You could fit seventeen soccer pitches on its mighty back. At five hundred metres long, it is over a hundred metres longer than the largest ships currently operating on Earth’s oceans (Maersk E-class container vessels). And it’s over three hundred metres high: there are only about fifty taller skyscrapers in the world today. An excavator is a single machine the size of a city block.
There is something awesome in the sight of huge, single-purpose engines like these. As a boy in the 1960s I was struck by the futuristic machines in Gerry Anderson’s Thunderbirds, such as the Crablogger in the episode “Path of Destruction,” which crashes through the jungle pulling out trees with its gigantic claws like a child pulling up blades of grass. Even today I can’t help but be awed when I glimpse the machines that clear-cut the big managed pine forests close to my home in northern England. A “harvester” will fell a tree with its chainsaw, rollers force the tree stem between “delimbing knives” that strip the trunk of its branches, and logs are cut to a specified length. A huge twenty-year-old tree can be processed in minutes. Later a “forwarder” picks up the logs to carry them to great heaps by the roadside for collection. There are humans in the cabs of these machines, but not a lumberjack’s foot touches the ground. It’s not quite the gigantic slash-cutter we see in Avatar, but the principle isn’t far away.
The unobtanium mines on Pandora resemble open-cast mining operations here on Earth—and especially the huge operations now underway around the world to extract oil sands.
Oil sands (also known as tar sands) are a kind of bitumen deposit. Bitumen is a dense and sticky form of petroleum that can collect in layers of sand or clay and water. Such deposits occur around the world, and in fact were exploited in ancient times in the Middle East for the water-proofing of reed boats, and creating Egyptian mummies. The world’s largest deposits are in Canada and Venezuela, each of which is said to have reserves equivalent to the world’s total reserves of crude oil. (Maybe this is why Jake Sully was sent to fight in Venezuela.) The Athabasca Oil Sands, in Alberta, Canada, have been the scene of the commercial extraction of bitumen since 1967. The Athabasca operation employs what are said to be the biggest power shovels and dump trucks in the world. The oil sands themselves are typically in a layer fifty or so metres deep, sitting on top of limestone strata. To mine them you have to clear the land of trees and brush, then remove what the miners call the “overburden,” the topsoil and layers of peat, sand and gravel, and then the extraction is done. This is roughly the technique used in the Pandoran unobtanium mines.
The modern extraction process, which requires huge amounts of energy for steam injection and refining, was until recently considered uneconomical—but that’s changed through a combination of better technology and rising oil prices. Production in Canada has grown to the extent that the country has become the largest contributor of oil and refined products to the United States. Environmental issues are regularly raised. State and national governments apply strict rules; for instance all such projects are required to implement a land reclamation plan. But environmentalists object that oil sands extraction processes generate more greenhouse gases per barrel than the production of conventional oil.
Meanwhile, at the time of writing there are plans to open up a huge iron ore mine in Arctic Canada, far to the north of any operation of a similar scale previously—an opportunity provided, ironically, by the global-warming retreat of the polar ice. Just as on Pandora, there is native fauna to be moved out of the way, including caribou, Arctic foxes and polar bears, and local people to deal with in the Inuit.
I suppose that if the world suffers the ecocide we looked at in Chapter 2 we can expect such operations to proliferate. Nobody would care about the impact on the environment, because there would be no environment to save, any more than on the lifeless moon. Certainly satellite views of the operations in Athabasca and elsewhere are starkly reminiscent of Avatar’s scenes of unobtanium mining on Pandora.
The principal unobtanium mine, humanity’s most distant industrial operation, is known as RDA ESM 01—RDA Extra-Solar Mine 01. Operators in sealed cockpits use chemical charges to break up the overburden, which is then removed with excavators, dozers and dump trucks. The unobtanium ore is removed with excavators and trucks, but a pure enough deposit can spontaneously levitate, requiring specialised belt diggers to feed into covered trucks. Over the thirty years of its expected lifetime the three pits of ESM 01 will eventually merge into a crater four kilometres across. But RDA is already looking at further deposits to develop.
All this is very plausible. Today we’re pretty competent at mining the Earth. And we are already working out how to mine other worlds.
In Avatar’s 2154, human colonies exist on the moon and Mars. And in our time there have been several studies on how you might mine these new worlds.
What is there to mine on the moon? Well (see Chapter 6), there’s water, maybe in trace amounts in the lunar soil, and helium-3, the right isotope of the element for the most effective operation of fusion plants, which is lacking on Earth. But these treasures are thinly scattered—it would be like harvesting dew—and strip-mining on a vast scale would be required. Imagine robot tractors crawling across the lunar surface, scooping up the regolith, processing tonnes of the stuff to sift out the minute fractions of water and helium-3, and perhaps baking the rest to extract oxygen. As for power, the unshielded sunlight is an obvious energy resource; perhaps areas of the wide, flat lunar seas could be melted to form gigantic solar-energy collectors.
The lunar conditions will invalidate much of our terrestrial experience of heavy industry and manufacturing; we will have to rethink everything. Moon dust, shattered by meteorite rain but unweathered, is extraordinarily abrasive, as the Apollo astronauts learned when they tried to make their spacesuit seals for their second or third moonwalks. The vacuum makes most lubricants useless; they would just boil away. And the low gravity causes problems with simple things like fluid flow, because of novel bubble effects in liquids. Lessons we learn on the moon, however, could be transferred to other worlds. It’s strange to think that low-gravity adaptations made to the feed lines on a Samson rotorcraft to enable it to operate on Pandora, for example, might have been learned on the humble moon.
In the Avatar future, in fact, RDA does maintain a lunar helium-3 facility. And the mining operations must have left a mark. Maybe by Jake Sully’s day the face of the moon in the sky, more or less unchanged for billions of years before humans came along, is pocked and scraped by mines, and the dust seas gleam, covered by tremendous solar-panel mirrors.
Meanwhile the best plans we have to get to Mars and back involve industrial processing of Martian resources from the very first landing—in fact, we would need to make a start even before humans get there. According to Robert Zubrin’s “Mars Direct” proposal, Mars would be reached with a wave of spacecraft capable of manufacturing their own return fuel from Mars’ carbon dioxide atmosphere, at a fraction of the cost of hauling that fuel all the way from Earth (the Apollo craft carried their own return fuel to the moon).
The key ingredient to support life, however, is as always water. And there seems to be plenty on Mars. As Percival Lowell suspected there is water-ice on Mars’ surface at the poles, just waiting to be scooped up. At lower latitudes, the spaceprobes have found evidence of water in the past: for example, what appear to be the remnants of gigantic, catastrophic flooding episodes, and perhaps even the tide marks of ancient seas. Where did all the water go? Perhaps it was drawn into aquifers in Mars’ interior by geological processes like the great subduction flows on Earth; Mars, smaller than Earth, cooled more rapidly, making its crust and mantle more able to trap and store water. Thus the first large-scale industrial operations on Mars are likely to be drilling for water—and the technical challenges there are almost as severe as on the moon.
From 2004 to 2007 I worked with a team from the venerable British Interplanetary Society on a design study of a manned base at the Martian north pole. It was a weighty study; project leader Charles Cockell is a professor of astrobiology at the Open University. And in the course of the study we worked on proposals on how you’d drill on Mars, specifically in our case because we wanted to extract an ice core. Just as on Earth, such cores, drilled from ice caps built up by snowfall year on year, contain records of climate variations reaching deep into the past.
Deep drilling, the kind you’d need to go down kilometres to a low-latitude Martian aquifer, is hugely challenging in terms of mass, power and manpower. Rotary drilling as we use on Earth is a tested technique, relatively low power, mechanically simple, and easily fixed in case of failure. But it requires a heavy support infrastructure, and in the dusty, cold, high-friction Martian environment any moving-part system would be vulnerable to many failure modes—lubrication failures, abrasion of bearings, loss of seal integrity.
A deep borehole will always require stabilisation to keep it from collapsing. The way this is done on Earth is to pump in a “working fluid” such as water or mud slurry. Water or mud will not work in Martian conditions; either would freeze immediately. Possibly some low-temperature lubricant oil would be suitable, but it would be very expensive to import such a fluid from Earth: you’re looking at tonnes of material, and if lost such a fluid load could not be replaced. The trick is to use working fluids produced from local materials, and the best bet may be to liquefy Mars’ carbon dioxide atmosphere. Unfortunately, carbon dioxide plus liquid water yields carbonic acid, a weak acid but corrosive; you would have to keep temperatures low enough throughout the borehole that ice chips do not melt, which will affect drilling rates, and to use corrosion-resistant materials.
This brief experience taught me a lot about the challenges of transferring heavy industrial operations to another world. In Pandora’s low gravity and toxic air, every tool, every machine, every material used will have to be redesigned, every technique re-examined.
And on Pandora the intense magnetic fields around unobtanium deposits are a novel significant problem for industry. Machines and tools can’t contain any ferromagnetic elements such as iron, cobalt or nickel because they would become so strongly magnetised their moving parts would seize up. Even some non-ferromagnetic elements like manganese become magnetic when combined with other elements, which limits the use of steel alloys and other materials. There are compounds that will work, such as tungsten carbide, but these are exotic and expensive. In addition, whenever you move a conducting material in a magnetic field electrical currents are induced. These can heat the material, interfere with circuitry, and interact with the global magnetic field to produce a resistance to motion. A miner swinging a pick would feel like he was underwater, and the faster he moved the hotter the pick would get—not that a human miner would be allowed anywhere near an unobtanium lode.
Still, by the time RDA reaches Pandora it will be able to build on decades of experience of mastering hostile environments in the solar system. And everything we learned on Earth, since the days thousands of years ago when we were chipping flint nodules out of chalk beds, will have been rethought.