I think it’s barely doable much less practical.
If you control a solid gold asteroid worth “quadrillions,” you’re a James Bond villain. You can blackmail the worlds banks any price for you not to flood the world with gold and crash world markets!
I can’t see how that would happen. If currencies were still backed by gold, then the blackmailer already has large amounts of money. Why give him more?
Since they aren’t, gold is just another commodity, so central bankers wouldn’t care. Or shouldn’t anyway. A large influx of gold would mess up the international exchange of gold, such as happens at the New York Federal Reserve gold vault, so they’d care to that extent. But not enough to give the blackmailer an indefinitely large amount of money and, if they’re smart, not any money at all. Just call his bluff. As pointed out upthread, it would cost him lots of money to bring the gold down from orbit. With a crashed market, he won’t make much on it.
Another example to show how it doesn’t seem economically feasible, even given massive improvement in space lift and space mining technology: there are things more valuable than gold, such as rare earths. In recent years there’s lots of talk about how shortages of rare earths can potentially reshape industries or entire economies, e.g: http://www.powertransmission.com/newsletter/0212/rare.htm
Maybe the most costly is scandium which at about $270 per gram is about 10x more than gold. If the Chelyabinsk meteoroid at 10,000 metric tons was identified in space long before the earth encounter and if was made of pure scandium it would “only” be worth $2.7 trillion – assuming that availability did not affect scandium prices, which it would.
Even if the technology existed to intercept this, deflect it and bring most of it to earth, and even if the price stayed at $270 per gram, that’s still only 15% of the US GDP, and 2.7% of world GDP. The total capital spending on space lift and mining to achieve this is unknown but it would be vast – maybe $1 trillion. As comparisons, NASA’s total inflation-adjusted spending since 1958 is about $800 billion, and the annual US DoD budget is about $600 billion. Basically it would require developing an industrial space infrastructure as far beyond the present as supertankers are beyond the ships of Christopher Columbus.
It’s not technically impossible to do, but I don’t see it as economically viable. And there are no asteroids made of pure scandium, lanthanum or neodymium. For the most part, these so-called “rare” earths aren’t really rare, just unconcentrated and difficult to mine. But you could terrestrially mine a lot of them for the $1 trillion it might take to develop robust industrial space mining.
One advantage of mining asteroids is that we would be extracting reduced iron, not it’s ore … saving the step of smelting …
I’m not sure what the typical velocity of these asteroids are relative to the sun … but we may find the energy required to match that velocity to Earth’s would be very large compared to floating the mass down to the surface … the problem with just dropping it in is that the initial collision isn’t with Earth’s surface, rather that collision is in the atmosphere …
The origins of Meteor Crater in Arizona was at first controversial … it took some time to find any remnants of the original meteor so widely this material was spread out … when I visited many many years ago they had on display the largest known chunk, a piece of iron about three foot long and a foot in diameter …
Once we develop the technologies to mine asteroids we may not need those resources anymore …
Sure. But it’s not that difficult or expensive to smelt iron from ore. The price of refined iron is a few cents a pound. And that’s here on earth, in space there’s no market what-so-ever.
Right on the first part, wrong on the second. Pieces of Canyon Diablo have been known about for as long as there have been people in the region–pieces have been found as Native American grave goods. Once the idea of meteorites was recognized be modernish science, they were known to be meteorites, and literally tons of fragments are likely in museums and collections.
What was controversial was the nature of the crater itself, which many thought was volcanic and the meteorite strewn field coincidental. (This was before diagnostic features for impact craters, such as shocked quartz and shattercones, were discovered.)
Another controversy involved the size of the impactor itself. A man named Barrenger bought the land containing the crater with the intention of mining the iron asteroid, which he thought to be as wide as the crater and buried deep under it. He spent the rest of his life and hundreds of thousands of dollars (back when that was a lot of money) attempting to drill down to the asteroid and never finding it. It wasn’t until near the end of his life that he asked physicists for help, who did the math and realized an asteroid traveling at interplanetary speeds would be much smaller than the crater left behind and that there was no mountain of iron under the crater.
Nitpick, but I believe escape velocity is about 7 miles per second, or 11 kps.
Also…We could use Mercury capsule style heat shields, with parachutes for final approach, or glider wings like the space shuttle had. Or retro-rockets, like the Mars landers. You don’t have to smack into the earth’s surface at full speed.
T’aint landing the stuff that’s the big problem: it’s going out there and finding it.
If we’re going to build any kind of large space structure, there will be a market for iron up there. That’s one of the main reasons for mining an asteroid – to get large amounts of structural material in space that would be extremely expensive to bring up from Earth.
Why would we build a large space structure? The concept is in the realm of science fiction because we’re nowhere near the circumstances to consider a giant space structure. Considering how to mine asteroids to build a giant space structure is putting the cart before the horse. I’m sure the low level of space exploration we do now will continue if we don’t mess up things on earth or suffer a global catastrophe but we are nowhere near the practicality of any kind of large anything in space. Long before we reach that point, if we did make space travel practical and beneficial beyond research we’d work from the moon or Mars. The need to ever mine asteroids is too distant in the future to know that it will ever come about.
We’re nowhere near the circumstances because we don’t have asteroid mining. But regardless of whether we wanted to build large space structures or not, we still need to develop asteroid mining technology, because it’s the same technology that we would use to save ourselves from an extinction-level impactor.
“Extinction level impactors” are on average tens to hundreds of million years apart. It isn’t really a serious worry.
But if one did happen when we weren’t ready for it, billions would die. You can’t just look at the odds for expected value; you have to consider the prize, too.
While the incidence of large (>50 m diameter bolides) is low, the resulting impact on human civilization would be potentially catastrophic, ranging from regional destruction on the order of millions of casualties and hundreds of billions of dollars in lost real estate and industrial capability to complete annihilation of all macroscopic life forms. We may not need to worry about it in the sense that we worry about annual flu epidemics, but it should definitely be on the laundry list of potential calamities that we should watch out for and develop the capability to avoid. And we do have the fundamental technology to develop this capability, at least up to nickel-iron astroids up to 1000 meter diameter, and water ice meteors up to 2000 meters in diameter. The costs of developing and deploying a usable deflection system are in the low tens of billions of dollars, less than what has been spend building the Ground-Based Mid-Course Defense ABM system against a calamity that no amount of diplomacy or deterrence posturing can avert if it comes. There is also the cost of deploying a solar-orbiting observatory between Earth and Venus orbit, or even better a constellation of highly elliptical solar orbiting satellites that can perform multiple roles including serving as an interplanetary telemetry relay/tracking/positioning system as well as infrared observatory for potentially hazardous objects. The cost for such a system (which is desperately needed to support multiple interplanetary missions and would be required for any human exploration mission to Mars or elsewhere) is about US$ 10-15 billion (or less if you have a large enough launch vehicle to carry the necessary solar and radiator panels, or can figure out how to use emerging inflatable structure technology to package spacecraft into the form factor of a Delta IV Heavy or equivalent).
As for the “practicalities of mining asteroids”, it is true that we do not currently possess the technology to capture, mine, smelt, and refine mineral resources form asteroids or comets, and that a vast infrastructure and novel processing technologies would be required for this. It is also true that it makes little sense to do so in order to bring minerals back to Earth. If we brought back a large amount of gold or platinum, it would only serve to depress the market and reduce the value of both the material being returned and in current Earth reserves. Even for relatively scarce industrial materials such as titanium or copper it generally makes more sense to use the material in more efficient fashion than to go to the expense of developing mining infrastructure specifically for those materials. There are a few very rare or difficult to extract refractory metals might be just valuable enough in an industrial sense to be worth returning to Earth (which could be done relatively simply by putting them into a blunt-base capsule with a simple silicate heat shield and allowing it to hard land at terminal velocity in broad ocean area to be recollected) but even this by itself is a hard case to make for the incredible costs of establishing a space-based industrial architecture.
Realistically the purpose of developing the capability to extract resources from space objects is to use them to support a human presence in space, and to this end the most valuable materials are water, organic carbon molecules, and nitrates. This is even true if your plan is to set up human outposts on the Moon or Mars, because these materials are not readily available in large concentrations and are absolutely required for any sustainable presence. (We currently ship all water and finished foodstuffs to the ISS by resupply rockets at the cost of thousands of dollars per kilogram, which would be completely unsustainable to support a large human presence even if you believe the projections of cost reductions from reusability of SpaceX or other boosters.) Of course, that poses the problem of how to develop such an architecture without having the resources to support people doing the work, which is a question that provides its own answer, to wit that for the most part it shouldn’t be people doing the work but largely autonomous spacecraft and robots, which can tolerate the interplanetary radiation and thermal environments far better than a human astronaut without requiring nutritional or environmental resources, can work around the clock, and can be abandoned or salvaged for materials once their useful life is over rather than being returned intact to Earth at great expense. The energy to do so comes from the same source as all of our other non-nuclear energy; that is, from the Sun, except not in the form of coal or natural gas but instead directly from concentrating solar radiation or using it to develop electricity. The Sun, of course, is available 100% of the time in orbit and without being filtered through a thick atmosphere, so it makes an almost ideal source of power continuous processing of materials.
A space-based resource extraction architecture would be expensive to develop and build, but it can be done in an incremental and progressive fashion, developing parts of the capability until some aspect of space resources, such as extracting ammonia and water for propellant and coolant, can be produced in situ and result in a reduction in overall cost for other activities. Many structures, including large scale habitats, can be built using reinforced water ice as the structural material (as I describe here) which is a lot easier to work than refining and fabricating structural elements from steel or aluminum, and frankly by the time we’re able to start building large structures and useful industry in space or on Mars we’ll probably be using synthetic allotropes of carbon or silicon as structural materials for many proposes.
Extracting resources from space resources, e.g. mining asteroids, is not “beyond the realm of the possible,” but it isn’t going to look anything like terrestrial mining with hydraulically powered heavy equipment, nor is it going to be as easy as the 'Fifties era image of sending up space miners to bust rocks and ship them back to Earth. It is one part of a necessary architecture for space exploration, both robotic and human. The necessity of this depends on whether you view developing an off-Earth industrial presence has utility, but there is no way to make a practical fiscal case for it in terms of terrestrial industries in any foreseeable timeframe. It is, however, a realm of virtually limitless resources with few concerns about pollution or waste products, and is coincident with the goal of also developing the capability to protect our planet from space hazards. And it is certainly a far better investment in the long term than nuclear arsenals and bombers.
Stranger
The biggest reason for mining water/ice (which makes it our main target) are as a life support material - water and oxygen - and that it can be dissociated into hydrogen and oxygen for rocket fuel. Talking of mining asteroids seem to ignore the massive amount of fuel needed to bring something down to earth orbit, plus the fuel to send the rockets out there to retrieve the stuff. That sort of maneuvering is cheaper than lofting material up from earth, but not by much… what’s more valuable (just like on earth) is a usable source of fuel energy.
The other thing to consider is manufacturing. Building sealed high-quality space habitats is not like laying railroad track or building steam locomotives. I suspect there’s a lot more technical work, and it probably isn’t something to be done in a spacesuit. We would need to develop the remote-controlled technology, the ability to manufacture high-quality sheets of assorted high-grade materials, etc.
I agree. It’s not that the same technology is even needed, it’s the continued research and continually reaching beyond our grasp that will save us some day if necessary. We don’t know what technology we will need or what we may need it for but it will probably be too late to start once we find out.
The good news: there’s the Interplanetary Transport Network which allows low energy routes around the Solar System. The bad news: it’s not exactly an express system.
One can envision an intermediate system with solar sails, ion drives, whatever that can transport materials to a semi-nearby Earth-Moon orbit in a more reasonable time.
A slowish transport system using gravitational keyholes will be a lot safer in terms of avoiding rocks hitting inappropriate places.
[Here](Live in fear? No. Be fearful during any encounter with a cop? Yes.) is a rather long YouTube video by a guy I follow on space stuff on the subject if you are really interested.
Well, a couple things here. First off, they might not want to bring the stuff back…they could use it as raw materials to build infrastructure in space. Just like water on the moon is valuable because you don’t have to bring it there from the Earth, there are a number of raw materials that would be very useful in space if you had acces to them and didn’t have to bring them up from the Earth’s gravity well.
Some things, though, you might want to bring back. Maybe precious metals or other rare resources that would be worth bring back. Those you’d bring back exactly like we bring humans back without burning them up…you basically make some sort of heat shield and put a parachute on them, then de-orbit somewhere you can recover.
You’d be wrong then. It’s currently beyond the realm of economic feasibility, and may remain so, but possible? It’s definitely possible. There are even some plus sides to asteroid mining if you can figure out a way to get the miners and equipment off the Earth and into orbit in a cost effective way.