At the recent Ad Astra SF convention in Toronto, Canada, I watched a panel discussion about asteroid mining, the problems and potential. I’ve posted about the subject before because it’s one of the major tropes of near-Earth space exploration predictions and stories. So is it really such a sure thing? The panel (including some PhDs, SF writers and a robotics expert) agreed that it will come down to profitability: revenue vs. cost. After all, you don’t go to the trouble of landing on speeding chunks of barren rock for the beautiful scenery.

There have been estimates that, although many asteroids will be mainly nickel-iron rocks, some will be very rich in platinum group metals, and a reasonable-sized one of those could contain far more than all of the known reserves of such ore on Earth. At first glance, that sounds promising. Of course, platinum and its relatives are costly because they’re rare—a sudden increase in the supply would be sure to cause prices to drop, cutting profits that might already be marginal. Especially when a Keck Institute of Space Studies report estimated that the cost of returning a 500 ton asteroid to low Earth orbit for processing would be in the area of $2.6 billion US. I’ve seen other projections that it would require more like $100 billion to create the infrastructure to make a mining operation, especially since a lot of new technology will have to be developed. Could such a venture possibly pay for itself, let alone make attractive profits? Companies like Planetary Resources and Deep Space Industries have already declared that they’re in the game, and the people involved are no dummies.

The costliest part of any space venture will be hoisting things up out of Earth’s gravity well into space, and returning things safely to the ground. So space mining may not become cheaper than mining for the same elements here on Earth until all of this planet’s resources are exhausted. If the intention is to return the mined material back here.

But what if the market for the ore you’re mining is out there? Shipping to and from orbital space stations, asteroid facilities, and even moon colonies would be much less costly because of the lower gravity involved. There are also a lot of other materials worth mining for, if your market is a space colony or interplanetary fleet. Water and oxygen for spacecraft fuel and human consumption would be valuable commodities, too, plus many more ordinary metals and non-metals. That certainly increases the potential for space mining, except it still suggests such an industry will have to wait until we make a big push out into space for other reasons, and thereby create the beyond-Earth markets.

One other thing that could possibly tip the balance in favour of space mining is if our current interest in corporate responsibility continues to increase. In the past, mining companies rarely had to factor environmental cleanup into the cost of their operations, but there seems to be a growing taste for making companies protect and rehabilitate the environment from the ravages of their ore removal and processing. If we ever start charging companies a realistic cost for their pollution and for remedial treatment of land and water, that just might raise costs to the point that bringing back ores from near-Earth asteroids becomes a better alternative.

Bottom line? I don’t think SF writers should scratch those grizzled space miner characters out of their stories just yet.