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-   -   Mining Asteroids (http://www.physicsforums.com/showthread.php?t=11361)

caumaan Dec20-03 03:19 PM

Mining Asteroids
 
I don't know if this is the correct section or not, but I'll let hosts and mentors decide that.

My question comes as a result of hearing a number of things floating around as to the possibility of mining asteroids for materiasl valuable to space colonies.

Do many asteroids contain materials useful to civilization in abundance, and could they be mined practically and safely?

enigma Dec20-03 07:18 PM

Re: Mining Asteroids
 
Quote:

Originally posted by caumaan
Do many asteroids contain materials useful to civilization in abundance,

Very much yes. A single largish (~1km diameter) metallic asteroid has metals worth more than the Gross Domestic Product of the world for hundreds of years.

Quote:

and could they be mined practically and safely?
Very much no. Space is the more inhospitable than anything you could think of. Any mistakes or mishaps (which tend to happen from time to time in mining... like almost everyday...) are almost guaranteed to be fatal, perhaps even for the entire crew.

Then there is the minor problem of getting the metals out of their orbit and into ours (or wherever you're planning on moving them to).

caumaan Dec20-03 08:43 PM

I don't suppose robotics would have any more application here than in current mines, would they?

enigma Dec21-03 01:47 PM

I'm sure they would. Automation is a huge engineering project, though.

Robots also wear out. It's not as dire if one of them breaks, but it would still kill the mission.

When terrestrial mining equipment breaks down, you call a mechanic. If an asteroid miner breaks down, it's a two year wait until a replacement can be sent (assuming you had one ready to go).

russ_watters Dec21-03 04:43 PM

Re: Re: Mining Asteroids
 
Quote:

Originally posted by enigma
Then there is the minor problem of getting the metals out of their orbit and into ours (or wherever you're planning on moving them to).
To be a little more specific, it costs roughly $10,000 / lb to put an object into orbit. Bringing it back costs roughly the same.

enigma Dec21-03 06:34 PM

I was actually referring to the costs to bring an asteroid from it's own orbit about the sun into our eccentricity and semimajor axis.

There aren't many metallic asteroids in low Earth orbit (unless you consider the ISS of course )

EDIT: If you had metals (caveat: with the means to manufacture them) in orbit, de-orbitting them would be foolish. You've got raw material in a place where it would cost exorbitant amounts to bring new raw materials. Just leave it and manufacture in-situ.

This is all assuming that if we've got the tech to mine asteroids in zero-G, we've got the tech to build stuff in zero-G as well.

selfAdjoint Dec21-03 08:44 PM

If you put the mined metal in a slow Hohmann orbit, with a delta-v at the end to put it in some stable solar orbit close to earth, then it couod be retrieved from there. Since it's so expensive to go up and down from the earth's surface, it would be more efficient to use the metal in space, either on the moon or in a lagrange facility.

caumaan Dec23-03 09:53 PM

So, beyond the huge materials found in asteroids (iron, nickel, etc.), what else can be found there?

enigma Dec23-03 11:43 PM

Water

Rare Earth elements

Organic molecules

You name it, there's an asteroid with it.

Nephtys Dec24-03 01:33 AM

Are any of those in large concentrations?

enigma Dec24-03 02:31 AM

It depends on the asteroid.

It's been a while since I read this book which went into great detail on extraplanetary resources (without being too "Pie-in-the-sky"... a big plus!).

Metallic asteroids have huge reserves of minerals and metals of all sorts.

Comets and (I think they're called:) carbonacious asteroids have reserves of organic molecules and water.

Nice coder Feb15-04 03:24 AM

Mine the van-allen belts for fuel, (i don't think something could go wrong with a magnet)
Charge your space-ship up like a capacitor, then wait for the ionised gas to start to 'stick' to your ship, you can then deionise it, compress it, cool it and SELL IT to other rockets $$

DarkAnt Mar15-04 08:52 PM

Great idea, now all I need is my spaceship...


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