asteroid mining

[sheehanja]

Hi Cecil, sorry partner you blew it on asteroid mining. The problem is getting up there. Once your out in space you have the advantages of zero gravity, the most fantastic source of free energy(THE SUN), with very close to absolute zero in the shade. We will be able power super-centrifuges to separate out basic elements in a state of purity impossible on earth.There are asteroids of pure iron, and "rocks" of pure water as old as our solar system. In order to comprehend the magnitude of what were on the brink of accomplishing you have to think outside of the box. This isn't earth mining, and the tools that will be used are currently on drawing boards and in development now.This is the new frontier. It isn't that we just want to go out there for the hell of it. We have to start our outward migration or our species will die out.


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LINK TO COLUMN: http://www.straightdope.com/columns/...aten-the-earth

[John W. Kennedy]

Among other questions, what do you make the centrifuge containers of?

[Learjeff]

Please post a link to the original article, Sheehanja. That's the convention here.

Anyway, another big part of the problem is getting back down.

BTW, while shade is cold as all getout, it's not conductively cold. You get only radiative cooling, so it's not as useful as say, really cold matter, from the standpoing of generating energy. Still, that's a useful differential to make use of, if only you could keep something in the shade. You can't do that with anything attached to an asteroid, unless you're also going to control the asteroid's rotation.

In any case, I expect the technical hurdles to be substantial, but so is the economic incentive. I'm 55 -- will I see it in my lifetime? Maybe!

[Irishman]

sheehanja, you are correct that space offers abundant materials and someday those could be very useful. Someday being the key.

Problems that Cecil addressed were related to mining asteroids and then returning the materials to Earth for use here. That poses the series of challenges
a) getting there
b) getting the asteroid back to Earth
c) getting the stuff from the asteroid safely to the surface without burning it all up on reentry or taking out Toledo

and then the relatively easy job of collecting it from where it came down to process like normal Earth materials.

You seem to be skipping the part about bringing the stuff back down to Earth's surface, and instead using it in space. That does eliminate some of the challenges Cecil addressed, but still has challenges of its own.

Namely, processing materials in space is going to be difficult, primarily because all of the processes for handling we are used to are designed to operate in 1 g. Centrifuges will be helpful - nee, necessary - parts of the process, but there's a lot more required than just a centrifuge. Like smelters, and high temp handling equipment, etc.

Plus, even if you can sort the raw materials into high purity base stocks, there is still the challenge of fabricating anything in space.

Consider the bulk of human space activity to date. Practically nothing has been fabricated in space. Even MIR and ISS consist of vehicles connecting together components prefabricated and assembled on Earth.

That is not to say those challenges cannot and will not be faced and met, but the timeline for those developments is much longer on human timescales than you seem to be giving credit. These steps will not occur in the next decade. We'll be lucky to see them in this century.

[Tom Billings]

Cecil, even the smartest guy on Earth should read up on the recent developments in an area before posting an article.

You said "The prize here consists of the so-called platinum-group metals, which besides platinum include osmium, iridium, palladium, ruthenium, and rhodium and are relatively abundant in some asteroids."

Actually, no. Not to the people interested in going after the asteroids, like Planetary Resources. They are interested, because they wish to make settlement of the rest of the Solar System possible. To them, the prize is water, first, Ammonia, and other ices come second, third is Carbon and then Iron and Nickel for building stuff third, siliceous materials for glass and heat shields, ...and then, the residue has Platinum group metals. Water is precious, because you can make hydrogen and Oxygen propellants from it. The Carbon can be made into graphene for composites with the plastics you can make with the first 3 things and later into graphene/diamond composites. These can be used to make spaceships headed out to the rest of the Solar System. Nickel and Iron can be used to make tankage at the EML-2 point you mentioned, or EML-1 as well, for the electrolyzed and liquified Hydrogen/Oxygen propellants early in the life of the Libration Point station. The platinum group metals can be used where catalysts are needed, or high temperature or corrosion resistance is a must.

*Then*, once the needs of space settlement are fulfilled, we can drop some leftover Platinum group metals down the gravity well. Till then, you would be sending them from where materials are expensive (if they are launched from Earth), to where they are, ...relatively, ...cheap. That's a dead loss. No business plan that does that will succeed.

Note that, as in human spaceflight itself, these "in situ resource developments" make sense *only* in the context of settling the Solar System. That is what groups like SpaceX and Planetary Resources are betting on. They have no faith that NASA will do it, certainly, because Congress would not fund it.

The idea of an asteroid mass small enough to process being a problem for altering the the Earth's orbit or spin disregards Newton's Laws. Gravitational force has an inverse square relationship to distance. The optimum asteroid being looked for right now, for rendering by the present technological base we have, is about 7 meters across, and a carbonaceous chondrite. It would mass between 350 and 1000 tons. It is over 300,000 miles away at the EML-2 point. Thus, each ton's effect on Earth's orbit or rotation is 75^2, or 5,625 times less than a ton floating on Earth's ocean. A 500,000 ton supertanker on the Earth's ocean has 2,812,500 times the effect that optimum sized asteroid would while being rendered down. Yet, no one has any fears of throwing off the earth's rotation, much less its orbit.

We have better things to worry about than this, ...like how to get a seat on the first ship leaving a Libration Point Station, for all the rest of the Solar system.

[Tom Billings]

Irishman said:

"Consider the bulk of human space activity to date. Practically nothing has been fabricated in space. Even MIR and ISS consist of vehicles connecting together components prefabricated and assembled on Earth.

That is not to say those challenges cannot and will not be faced and met, but the timeline for those developments is much longer on human timescales than you seem to be giving credit. These steps will not occur in the next decade. We'll be lucky to see them in this century. "

If we depend on governments to do them, yes. There is no political profit in doing the settling of the Solar System so many still see as "Buck Rogers", or any of the technology developments needed for that, ...and there won't be for some decades.

Still,if we depend on people intent on settling the Solar System, no. That is what groups like SpaceX and Planetary Resources are intent on. That is what people like MadeinSpace are intent on. Experiments are already done in freefall on crude versions of the sort of additive manufacturing tech needed for making things in Space.

More are funded, privately, and even a small government experiment, at ISS, ...successfully, I might add. Even when you can only add plastics to make a part, there are lots of plastic parts on the ISS that can and do break. Not having to wait to get them manifested and sent up on Progress, Dragon, or the other transports soon to come, has been a boon to ISS commanders and crew.

Once initial proofs of usefulness are established enough, we will see some space station, probably one of the Bigelow "Sovereign Lease" stations, become the site for the first in-vacuuo experiments at making additive metal manufacturing work in the vacuum of LEO. This will be far more flexible than the cramped and very expensive confines of the small vacuum chambers used today for additive manufacturing in metal. Soon enough after that, we will see this tech applied at the EML-1 Libration Point, to printing out large parts of robot probes, from the materials brought back by groups like Planetary Resources. The next step will be printing whole ships for crew, who will begin the settlement of the Solar System.

[Musicat]

Tom Billings, your total lack of cites speaks volumes. Are these just your opinions or can you back them up with something? (And the quote function might be useful.)

Most likely, this is the column being referenced.

[Tom Billings]

Musicat said:

"Tom Billings, your total lack of cites speaks volumes. Are these just your opinions or can you back them up with something? (And the quote function might be useful.)

Most likely, this is the column being referenced."

Yes, I know this is the asteroid mining thread. I was replying to a crucial portion of the original article in one post, and to a small portion of Irishman's comment in another.

What does your "quote" function do? This is my first time here.

As to cites, I am speaking of things that anyone who has paid attention should know.

The composition of carbonaceous chondrite asteroids is well characterized. So that should hardly be any great search.

Even wikipedia has a bit:

"Several groups of carbonaceous chondrites, notably the CM and CI groups, contain high percentages (3% to 22%) of water,[2] as well as organic compounds. "

at http://en.wikipedia.org/wiki/Carbonaceous_chondrite

and "C-type asteroids are carbonaceous asteroids. They are the most common variety, forming around 75% of known asteroids[1], and an even higher percentage in the outer part of the asteroid belt beyond 2.7 AU, which is dominated by this asteroid type. The proportion of C-types may actually be greater than this, because C-types are much darker than most other asteroid types except D-types and others common only at the extreme outer edge of the asteroid belt"

at http://en.wikipedia.org/wiki/C-type_asteroid

The comments on additive manufacturing are typified by knowledge at pages like:

http://madeinspace.us/indepth-review...s-on-space-com

It really is not difficult, though I know my continual activity has some advantages over the years.

Just what sort of detail are folks at this site looking for in cites?

[Musicat]

Cites are good. Basically, in GQ or Cecil's Columns/Staff Reports, if you make a claim, it's wise to back it up with a cite or two, and the source should be good (Wikipedia is medium-good, scientific abstracts are better). If you wish to refute Cecil (yes, Cecil is God here, but even God isn't perfect), you need the best cites of all, and many of them. You may not agree with Cecil, but I can assure you he doesn't post without a shitload of research, a lifetime of experience, and a lot of expert help.

Quotes are also good. If you click on the "quote" button near the right-bottom of a post, it will put that post in a quote box, ready for your comments, additions or edits, and you can see the code that needs to be used. Try it, you'll like it. You can see the results with your preview, then fix stuff and preview again.

This is a quote in a quote box.

[TubaDiva]

It's always the polite and considerate thing to link to the column being discussed.

http://www.straightdope.com/columns/...aten-the-earth

[Irishman]

Originally Posted by Tom Billings

Yes, I know this is the asteroid mining thread. I was replying to a crucial portion of the original article in one post, and to a small portion of Irishman's comment in another.

That line wasn't really addressed to you. Convention here is to add a link to the original column so we are all on the same page, so to speak. That is especially important when the column reference falls off the main page. Sheehanja neglected the link, and the rest of us failed to add it as well.

What does your "quote" function do? This is my first time here.

Quote is a board function that easily places text you are quoting in an offset box, so it is easily distinguished. It makes reading who said what a little easier. You can quote by clicking the "Quote" button at the bottom of a post you wish to quote. You can also use the button next to it to quote multiple posts and then reply in one reply. Once the edit window is open, you can edit the text to omit irrelevant comments or whatever.

You can also manually quote tag by using [quote][/quote] tags.

As to cites, I am speaking of things that anyone who has paid attention should know.

As an enthusiast, you are far better informed than most of your audience. It is considered good form to provide links to websites that back up your statements, so people less well informed can see on what basis you make your assertions.

The comments on additive manufacturing are typified by knowledge at pages like:

http://madeinspace.us/indepth-review...s-on-space-com

Thank you, that is the kind of cite we like. That site is interesting, I was aware of 3-D printing technology, and the ability to cast some metals. But I was not aware of this company and their putting one of these as an experiment for ISS. Yes, this will be exciting and very beneficial technology to have, both for ISS support, and for space manufacturing. Scaling up to make structural objects is much simpler than the original conceptual development to practical application.

Originally Posted by Tom Billings

Actually, no. Not to the people interested in going after the asteroids, like Planetary Resources. They are interested, because they wish to make settlement of the rest of the Solar System possible. To them, the prize is water, first, Ammonia, and other ices come second, third is Carbon and then Iron and Nickel for building stuff third, siliceous materials for glass and heat shields, ...and then, the residue has Platinum group metals.

That is a good addition. The primary goal is not, as the original question asked, about mining space for materials to use on Earth, but rather mining space for materials to use in space. And exploration and colonization in space is a different game than bringing asteroids to Earth's gravity well.

The idea of an asteroid mass small enough to process being a problem for altering the the Earth's orbit or spin disregards Newton's Laws. Gravitational force has an inverse square relationship to distance. The optimum asteroid being looked for right now, for rendering by the present technological base we have, is about 7 meters across, and a carbonaceous chondrite. It would mass between 350 and 1000 tons. It is over 300,000 miles away at the EML-2 point.

Correct, distance and size are important when looking at potential effects to Earth's orbit. The original question assumes that mining will require very large asteroids. From a certain standpoint, it makes sense. If you have to go and obtain materials and then drag them back to Earth for use, then it is not very cost effective to hunt down small boulder-sized asteroids. Far more efficient to get mountain- or continent-sized asteroids. Less travelling here and there. So the concern is valid if one is following the assumptions that one is bringing the resources to Earth.

Originally Posted by Tom Billings

If we depend on governments to do them, yes. There is no political profit in doing the settling of the Solar System so many still see as "Buck Rogers", or any of the technology developments needed for that, ...and there won't be for some decades.

Still,if we depend on people intent on settling the Solar System, no. That is what groups like SpaceX and Planetary Resources are intent on. That is what people like MadeinSpace are intent on. Experiments are already done in freefall on crude versions of the sort of additive manufacturing tech needed for making things in Space.

I will be happy to be proven wrong. The challenge for these groups is to make a sustainable financial endeavor.

[Musicat]

Originally Posted by TubaDiva

It's always the polite and considerate thing to link to the column being discussed.

http://www.straightdope.com/columns/...aten-the-earth

Amazingly similar to the link in post #7.

[aruvqan]

I was disappointed to find this wasn't about Eve online, I am always looking for ways to improve my indy skills ....

[masterquinn]

trillions of dollars in minerals eh? wouldnt that bankrupt the planet?

1 company, say company X makes (for easy numbers sake) 1 trillion in profit. X company can now afford many more miners, and can bring many more rocks to the planet, makes say 5 trillion more dollars.. now what happens? mass inflation?

Sounds like a monopoly waiting to happen...

And with say 20 - 30 more rocks - now easily affordable, how will the ocean tides be? could they theoretically pull on the the moon itself?

[Irishman]

Supply and demand means that if someone shows up with one of those huge rocks, the supply of that item will skyrocket, while the demand will remain constant. Ergo, prices will fall dramatically. The more rocks, the lower the cost per pound.

That is what Cecil references about the Spanish and the gold market.

Ergo, the more successful mining of that sort is, the less profitable it becomes.