NASA On Mining Extraterrestrial Sources

FortKnox writes "Looks like something from the game "Homeworld", but NASA discusses mining ore from planets/asteroids or any other source of "Cosmic Dirt"." I remember debating this idea in high school debate - it's a wonderful idea.

Comments

Uh. No. Re:mine WHAT?

[WolfWithoutAClause]

"I'm sorry, I don't buy it. Space travel costs are in the billions of dollars per ton right now. A metric ton of aggregate crap... you can mine out of my back yard."

Actually the costs to LAUNCH is "only" ~$2600/kg. That's $2.6 million/tonne, that's 3 orders of magnitude less than you quoted. And although that still sounds expensive, it usually turns out that what is launched costs 5-10x more than that to develop and build; so launch costs aren't the issue.

But that's launch. There's many reasons to think that space transport is going to be many times cheaper than that- if you use space resources to move around; IN space, rather than getting INTO space, the costs are much, much lower. For one thing, reusable interplanetary craft are pretty trivial to design- fully reusable launch vehicles are harder.

Incidentally, some materials are 'ungodly' expensive. Check out the price of platinum group materials- they run at over $500/ounce.

Oh yeah, BTW the underlying cost of launching something into space are under $10/kg. That's more than the fuel costs. We're a long way from that at the moment- but from my studies, there's a pretty convincing argument that that's mainly because the launch rate is so low right now (the costs are, surprisingly, roughly fixed, and amortise across the amount of launched mass).

I'm expecting the launch cost to go down by atleast 4x in the next ten years, and to do the same in the ten years after that. That will put Space Tourism in the ballpark of a Concorde flight.

Not NASA leading the way

[Cujo]

The posting implies that NASA is leading these studies. Not at all. It's primarily the academic community and non-profits like the Space Studies Institute and the National Space Society. NASA generally puts its mouth where its money is, and that's the ISS, which does little or nothing to help advance the cause of space development.

Given the very poor ROI of the ISS, who would seriously trust NASA to lead the way on lunar, asteroid and cometary resource exploitation? The best they can do is sponsor science missions so that we can understand what these resources are and where. In fact, they are doing that.

Like any conference, there will be loads of good and not so good ideas presented, but the fundamental logic is the same: it makes no sense to build things in space with materials brought from the ground. There are loads of materials on the moon (and no biosphere to damage) that have the potential to supply a large proportion of a spacefaring civilization. Big question is, do we want to be a spacefaring civilization?

Re:Asteroids = $$$$$

[WolfWithoutAClause]

The counter argument is that the asteroid isn't much more valuable than the rock in your backyard- it has much the same abundances; although more platinum group metals.

But the counter-counter argument is that the asteroid has something you don't have in your backyard- a continuous supply of mostly free solar energy. Smelting on the earth is enormously expensive. Smelting at an asteroid only needs a big sheet of foil and you can obtain ~5000C.

Solar ovens give 1.6 kw/m^2. That's a lot. On earth solar power is less than 1/6 of that due to weather, oblique angles, atmospheric effects and this phenomena called 'nighttime'. 200 watts isn't much. 1.6kw is getting respectable.

(And no- solar ovens are not hard to build- they don't require any kind of high precision; but they are not used much on earth chiefly because of weather and mounting/pointing issues, in zero gravity this is not an issue.)