What resources could be gained from asteroid mining that would be worth the effort?

Question

Obviously asteroids are abundant in many of the raw materials we use today, but considering the (presumably) large expense involved in mining from asteroids it may not be worthwhile to mine some materials since it is more cost-effective to get them on Earth.

There are mainly three issues here:

1. What is the approximate cost to develop an asteroid mining enterprise?
2. What would the approximate on-going cost of operations be?
3. What resources are available on asteroids that would be more cost-effective to mine that way (considering the above expenses) than to obtain using conventional methods?

I don't know if any of these issues have been addressed in a technical paper or discussion to this level of detail, but I would appreciate as much detail as possible.

(Another matter of consideration is when we start developing the asteroid enterprise and how long it would take to develop, because these things affect both the cost and benefit. Please take these into account in your answer.)

Edit for clarification

I'm looking primarily for asteroid mining of resources for use on Earth, though an answer addressing asteroid mining of resources for use in space would also be interesting. Obviously the answer to the latter would be very different since it is probably more worthwhile to mine resources in space for use in space.

Answer 1

NASA has actually published a study on this. This study was the primary motivator for Planetary Resources to start its work on mining an asteroid. And there is more work being done by NASA to learn more as well. And there's the approach that Planetary Resources has set in place, which seems to be the best overall approach.

The first thing that should be noted is that Asteroids have large amounts of precious metals. Estimates show that even a small asteroid could have a fortune in Platinum, at least at today's prices. Work would need to be done to ensure that the value didn't plummet the economy. But, there are other options as well out there as to how an asteroid could be valuable.

There are 3 primary types of asteroids. C-type, S-type, and M-type. The latter two contain significant amounts of iron, and the C type carbon. Now, metal on the ground is quite cheap. The cost of Iron Ore is about \$115 per ton. It would therefor be difficult to make money on Earth using Iron Ore. However, there is an alternative way to make money. The Falcon 9 has a cost per pound of \$1800+ if loaded to it's maximum capacity. Thus, if you can make something useful in space of your asteroid, it's value has suddenly increased dramatically. The key for the short term profitability in space is the ability to manufacture and otherwise assist satellites. The amount of money that can be made increases dramatically if you can pull it off. Rocket Fuel, which could easily be made from an asteroid, has the same cost of \$1800/pound, if you can get it to the source. It might even be worth more, as fuel would extend the lifetime of the satellites, which are significant investments.

So, what does it take to make a space mining operation profitable? Manufacturing. If you can develop an autonomous set of manufacturing robots, then you might be able to make something work. There is a number often quoted of \$2.6 billion to break even, but that depends on making these advanced robotics work. It could work, but I think only time will tell.

There is also a whole world of microgravity manufacturing possibilities which has barely been touched. It's far easier to make some things in microgravity, but we haven't really explored that space very much yet.

The closest we've done to real space mining is the Apollo program. In total, it brought 382 kg of rocks, for a cost of around \$125 billion in today's dollars. Asteroids would be cheaper to go to than the Moon, and using unmanned spacecraft should make it cheaper, but the proven numbers we have gives a cost of about \$9200/ounce (\$325/g). If that cost can be reduced, which should happen by making it unmanned and the primary mission, then gold could be profitable fairly soon.

The bottom line is, it's a long time before the Earth mining industry will be affected by Space Mining, but it would likely significantly affect the aerospace industry, moving operations to on orbit. And some day, some of those materials will return to Earth.

Answer 2

This is somewhat a matter of opinion, but I believe the answer to your title question is "NONE". That's why there aren't any major mining companies that are even remotely close to doing this. If there were resources on asteroids that merited the costs of mining them, then such companies would probably start to do so.

The first two questions you raise (the ones labeled #1 and #2) are not really answerable in a general sense. There are so many parameters affecting the costs (either development or operating) that any "general" answer would be pretty much meaningless.

That being said, there may be a time in the future when mining asteroids becomes economically reasonable. And despite the current economics, there have been plenty of serious attempts to start asteroid mining companies. The most notable presently is Planetary Resources, Inc.. Despite the all-star line-up, however, none of the people involved have any mining experience (as far as I'm aware). They are mostly space enthusiasts who believe strongly in the long-term potential of exploiting space commercially. I would argue that they are motivated largely by their ideals, rather than by economics (which isn't a bad thing, and I wish them success!).

Answer 3

The answer will depend on how we deplete our Earth resources.

I'm fairly sure uranium would be extremely welcome since I've seen estimates that we have maybe 100 years worth of its supply, although it's yet to be found in bulk in space.

While iron is abundant on Earth, smelting its ores is costly both environmentally and financially, so a "space forge" using meteoritic iron ores and processing them into ready products (and delivering ready forms directly to the customer through aerial drop) would be viable. In this case lack of gravity and air could reduce the costs.

Lunar He₃ is targetted as a potential energy source.

Still more in realm of sci-fi than actual science, but Jupiter's vast hydrogen supply could provide energy both for long-distance space travel and for power for Earth (although projects of "beaming power" (powerful masers) are more viable than just hauling hydrogen).

In more distant future, when sources of hydrocarbons on Earth are depleted, methane sources like Titan may become economically viable.

Currently, though, robguinness' answer "None" is correct. We're still quite a bit away from the break-even point of costs vs profits. I'm sure once "cheap" sources of energy (both oil and uranium) get depleted, that will begin changing rapidly.

Answer 4

Not a single poster has mentioned cobalt. Chondritic metal is an alloy of siderophiles (“iron-loving” elements), the next after the host iron being nickel, then cobalt. Nickel is not particularly precious, but not worthless either. (Hence, nickels.) Cobalt, however, is odd enough (on Earth) to raise logistics issues.

Magnesium is also VERY common, but it’s mostly bound as ores, and not any better than terrestrial ore.

As the OP clarified, the real value is in-space material. The absolute first resource is…shield mass, for use as micrometeoroid/ionizing radiation barriers. Next comes water, as direct propellant (thermal rockets) or propellant feedstock. We could go on and on- silicates for solar cells, agricultural medium, etc. but all left in space.