If you're going to mine in space, the last thing to do is bring minerals back down to earth
Miners! In! Space!
Following on from Planetary Resources, the asteroid-mining company formed by a small group of billionaires, engineers and space exploration enthusiasts including Titanic director James Cameron and Google co-founders Larry Page and CEO Eric Schmidt, a second firm, Deep Space Industries, has revealed plans to launch a fleet of spacecraft to strip resources from small asteroids passing close to earth.
Announcing the proposals, chairman Rick Tumlinson said that resources locked-up in nearby asteroids were sufficient to "expand the civilisation of Earth out into the cosmos ad infinitum".
The first prospecting missions with what the company call FireFly and DragonFly probes could hitch a ride into space on the launches of large communications satellites, it said.
The company hopes ultimately to land spacecraft on hurtling asteroids and have them scrape up material for processing in space or for return to Earth for sale. One long-term idea is to build a space-borne manufacturing facility that takes in asteroid material, processes it into usable alloys and other substances, and makes objects with the material via a 3D printer.
The crucial thing to realise in order to make space mining work is that, surprisingly, most minerals are far more valuable if they are left in space.
For all the talk — repeated by Deep Space Industries — of "asteroids with more gold and platinum in them than the human race has used in its entire history", the company has a ready made market if it takes advantage of the fact that it costs roughly $20,000/Kg to launch something in to space. That means anything it can mine up there which has the slightest bit of use in space exploration — water, oxygen, hydrogen in particular, but many other common minerals — can be sold for around that amount to other companies trying to do things in orbit.
In fact, until that launch price drops — perhaps because of a space elevator (we should build a space elevator) there is no reason to mine anything for earth's consumption at all. Even platinum, one of the most valuable things they could find, is only worth $50,000/Kg on earth right now. The costs getting a Kg of platinum just from orbit to ground level are pretty high — though obviously not as bad as the reverse trip — but once you start bringing it down in any large quantity, the market will be flooded. Unless Deep Space Industries are planning on become a sort of Star Trek De Beers, controlling the supply of precious metals with an iron fist, they'd do better steering clear of the shiny stuff and focusing on helping future astronauts breath and drink.