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From the submitted article's last paragraph: "None of this makes the moon a wellspring, and it would have a long way to go before it became a remotely hospitable place." The remainder of that paragraph speculates away the logical consequences of that sentence. Overall, the key fact about permanently shaded areas of the Moon, the places with the most water (and not much at that), is that they are extraordinarily cold. Figuring out ways to mine and extract the frozen water in such dark and cold conditions might be a lot more expensive and technically difficult than simply bringing along water from home.

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Figuring out ways to mine and extract the frozen water in such dark and cold conditions might be a lot more expensive and technically difficult than simply bringing along water from home.

Best guess [1] for cost to lift a kilo/liter to orbit is $20,000 per.

Have to be real expensive to mine water to make it more expensive than shipping the stuff from the Pacific.

[1] It is surprisingly hard to tease out data on this value: government accounting is partly to blame. Also: FedEx does not (yet) list their rates for 'delivery to LEO'

I don't think that the 2012 cost of transferring water from Earth is relevant. If we're in the position of having colonies on the moon, then I assume that our technology and techniques will have improved to the point that transferring anything from the Earth to moon will be significantly less. Otherwise, we wouldn't have colonies on the moon.

This, of course, assumes colonies on the moon. Personally, I doubt we will ever have them. But if we do, I think it's also reasonable to assume that the cost will have been lowered significantly.

I don't think that the 2012 cost of transferring water from Earth is relevant.

Think of it as a benchmark.

We know X costs Y, so Z needs to cost less to be viable.

This is useful even if the value of Y declines. It ought to: there is money to be made in reducing transaction costs.

I'm more bullish on the prospects for living off-world.

If we can get there for a reasonable cost, if it's possible for people to live there, people will go.

It's an upper-bound, sure, but I don't think it's relevant because I think that if we have a moon base, it's going to necessarily decrease by orders of magnitude. At that point, we're dealing too much uncertainty; we don't know how to mine water on the moon, and we don't know how much the transportation cost will decrease.

It's going to "necessarily decrease" in inflation adjusted terms: Sure. It's going to necessarily decrease by orderS of magnitude? No, I think that's too strong. Our most wild technological extrapolations only cover 2 or 3 orders, tops, and there's no guarantee they can or will be built. I do not see prices dropping to 2 cents per ton any time soon.

On the flip side, yeah, actually we can make a pretty good guess at how to mine this water. We actually are pretty good at mining. Run in through a machine that literally boils it out. Done. Throw the leftover rock in a big pile. At 2% concentration that's more than enough to get you started, it just needs energy, which is also fairly easily to get in this context. A real miner might do something else but that would certainly work.

My claim is that if transporting a liter of water to the moon does not decrease by orders of magnitude, then we won't have colonies on the moon. No colonies on the moon mean no reason to mine the water.

In other words, I think that the only circumstances in which we would want to mine water on the moon, transporting water would be orders of magnitude less expensive than $20,000/liter.

The "unknown" bits I was referring to are the infrastructure required to be on the dark side of the moon.

It's kind of hard to put a simple number on that (of course, you could have done tons of research to support this, I'm not sure). But it turns out one of the ordinary byproducts of ordinary rockets is water, which is why all space food is dehydrated. This means that if you sent a rocket with nothing on it at all (zero payload) it would arrive at the moon with water.

Of course I don't know how much and it is still likely to be ridiculously expensive.

of course, you could have done tons of research to support this, I'm not sure

Not tons, but some, in support of work for a prior employer.

But it turns out one of the ordinary byproducts of ordinary rockets is water, which is why all space food is dehydrated.

More like 'a particular fuel that can be used in a rocket is ..'

But actually I'm not sure what you're talking about, sorry. Can you expand and correct my knowledge?

Rocket fuel goes out the back end, pushes the rocket forward, right? The water is stored in tanks which astronauts draw out to rehydrate their tang?

Ok, so I'm a little sketchy on where I heard it originally, bu I think I was watching some sort of space show that said that hydrogen and oxygen mix together to propel a rocket but they capture some of the emitted water vapor and turn it back into water for other uses. I can't find specific reference to this recycling on the internet, but liquid hydrogen is a commonly used rocket propellant.

http://en.wikipedia.org/wiki/Liquid_hydrogen

Is that $20,000 for the cost from the earth to the moon?

Because I would guess you could escape moon gravity and fall towards earth for a lot less than $20,000 per liter.

And large chunks of ice, hurled from the moon, would just melt in our atmosphere. Which is OK if you don't care to deliver water to anyone in particular and just want more of it on earth. You know, in case global warming doesn't raise sea levels enough.

Just send solar powered robots at in initial cost of $20,000 per kilo to mine the ice, and have them hurl it at earth for a lot less than $20,000 per liter.

uh, you're sending water the wrong way.

$20,000 is cost of taking Earth water into space, and hopefully dumping it on the moon. That's compared to however much it is for existing moon-dwellers to setup and mine water from the moon.

Well, that dark problem at least seems pretty easy to solve at least.

Please indulge my ignorance... Maybe a chemist or someone better versed can answer; are we close, or is it plausible to construct a star trek like replicator to rearrange atoms to form new substances such as water?

It's complete science fiction at this point and there are scientists that argue it will stay that way forever.

http://en.wikipedia.org/wiki/Drexler%E2%80%93Smalley_debate_...

But who knows. Maybe when society is so advanced that we have infinite power from controlled fusion, extremely accurate and high powered lasers and magnetic field generators, and quantum computers, we'll be able to build a box that moves around individual atoms to construct something.

Though that doesn't mean that nanotechnology is impossible. In fact, nanomachines in the form of microbes precede any macromachines. We are getting better and better at controlling microbes. Though we won't be able to use genetic programming on microbes alone to make a cake or steak from scratch.

You can form water from recombining oxygen and hydrogen. Or from material that contain oxygen and hydrogen.

Making water out of anything else, is possible in molecular quantities at an exorbitant price using a particle accelerator (or so). So in practice, impossible.

A Star Trek Replicator, even one that doesn't transmute different elements into each other and just re-arranges them, is a long way off. The best current design we have is called an ecosystem and uses plants, fungi, animals, other life forms and sun light.

To mostly mirror what eru said, we can easily combine hydrogen and oxygen just by burning them together.

You can also extract amounts of oxygen and hydrogen from more complex substances and turn them into water through the magic of that science we know as Chemistry. You should expect that this will generally take a bunch of energy, though.

Nanotechnology has the potential to let us construct much more complicated sorts of chemical structures. It would be really neat, but wouldn't really change how much energy it takes to separate water out of other materials, and would probably be a lot less energy efficient than standard industrial methods.

Sounds like a job for Thorium Man!

http://www.ted.com/talks/kirk_sorensen_thorium_an_alternativ...

Isn't there lots of Thorium, and other fissionable and fusible material on the moon?

That was a point (iirc) in the linked video. Yes, it appears the all the required raw resources are there -- now we just have to do it.

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