I already pointed out that hydrogen and oxygen was available. If you want water in space, you can cook up a fresh batch.
Errmmm . . . where, exactly, are hydrogen and oxygen available in space? I don’t mean, for instance, the hydrogen mantle of the Sun, or the diffuse clouds of hydrogen a Bussard ramjet might scoop up for fuel. I mean hydrogen and oxygen in accessible and usable quantities. Is there oxygen buried in the crust of the Moon? If so, how would you extract it? And then, where do you get the hydrogen?
The lunar regolith is 46% oxygen by weight. Tied up in silicates and oxides. So it’s going to take some energy to get.
Hydrogen is much scarcer - about 1 ton per 1000 tons of regolith. However, it free hydrogen from solar wind, and it might be easy to harvest. Imagine a nuclear powered vehicle with a big fork on the end, driving around sifting and heating the soil. The process would release the unbound hydrogen and HE3. The hydrogen can be used to make water or rocket fuel in combination with Oxygen, and the HE3 can be shipped back to Earth for fusion fuel, assuming we get that working.
The key is power. Methinks we’ll want to build some big-ass nuclear reactors on the moon. An excellent place for them. With enough power you can do anything - melt soil into glass for building materials and fibers, extract lots of chemicals from the soil, make water, dig tunnels, etc.
The Moon may turn out to be an excellent place to colonize. There are giant rilles that are totally covered and insulated that might make great places for colonies. The moon is stable, and those underground tubes should last for millions of years. Seal up the ends, use power to melt the sides into glass to make them airtight, and you’ve got a lovely home maybe 75 miles long and thousands of feet wide. You could build a small city in one.
And there is water ice on the moon - the lunar Prospector spacecraft has already discovered it at the poles. The question is how much. Maybe a little, but perhaps as much as six billion tons. The latest data indicates that there probably isn’t that much, though. Six billion tons implies vast sheets of ice hidden inside perpetually dark craters. The lunar prospector crashed into one of them hoping to kick up an ice plume that could be detected, but none was. Since then, other measurements from Earth have failed to pick up widespread signs of water.
But that doesn’t mean the water isn’t there. Instead of vast ice sheets, it’s probably just distributed through the soil in granular form in the dark craters. So instead of 6 billion tons, perhaps there’s only a hundred million tons. That’s still a lot of water.
6 billion tons of water, by my calculations, is about 7,000 cubic miles of water. In comparison, Lake Superior contains about 3,000 cubic miles of water. So we’re talking about a LOT of water. Enough for millions of people. Even 100 million tons of water is enough to support a large population.
And that’s just the water tied up as ice from comets. If you have to, you can extract hydrogen and oxygen from the regolith and combine it.
Let us not forget possible petroleum reserves in astroids and on the moon predicted by the theory of aboitic petroleum origins.
Well, they’re there. Admittedly they’re not in the immediate neighbourhood.
Comets have hydrogen and oxygen. And they’re low gravity objects so it’d be easy to strip resources of them. The downside is they’re most common out in the further reaches of the solar system like the Kuiper belt. But what’s a few billion miles?
Seriously, the most likely way to collect these resources would be with AI-controlled ships. They’d make a long (one way) voyage out and then take up an orbit out around 40 AU’s. When they detect a likely comet, they’d give it a push towards the sun (remember gravity’s on out side here). A few years later, megatonnage of raw material arrives and we collect it.
We have the technology to do this now if we wanted to. If it sounds “pie in the sky” it’s nothing in comparison to plans to mine Oort objects - now those are a long ways away.
When you say 6 billion tons, thats like saying theres more gold in the ocean here on earth than has ever been mined. The problem is if it’s so sparsely distributed that it would almost certainly be unprofitable to mine. There would have to almost certainly be some sort of deus ex machina of the nanotechnology or free nuclear fusion kind to even posit doing things like extracting hydrogen from regolith. And, IMHO, most of the hype surrounding both of the aformentioned technologies is precisely FROM future geeks who need something to justify schemes like extracting hydrogen from regolith.
I just don’t see it. Not for a long, long time. My guess is Space Tourism is about the only thing we could expect in the next 100 years showing any significant potential for growth, but I’m not sure if that industry could survive the inevitable consumer recoil when one of the space habs/hotels goes “PHHHHTT!” and a small crowd of billionaires bites it. Margins are likely to be tight.
I read someplace that building a rotating space station of the size pictured in Kubrick’s 2001 ASO would bankrupt the world economy. It’s just too damn expensive to get all the needed stuff into orbit, much less out of Earth’s gravitational influence, to imagine any kind of profit-driven industry. Net-energy-producing nuclear fusion, and the resultant endless supply of cheap liquid hydrogen and oxygen might help, but we need that technology first. Who can say when we’ll get it?
Space elevators are all well-and-good, but what are they going to be built out of? Nothing extant fits the bill. Km-long carbon nanotubes are a nifty idea, but I’m not holding my breath until somebody actually can manufacture such a thing. Despite all the hype, that sort of technology could still be decades away for all we know.
All the industrialized nations put together may not be able to afford a modestly-sized permanent moon base for research purposes, currently; or they lack the will and mutual respect to embark on such an endeavor. There’s no way private industry is going to foor the bill for something so massively expensive.
Nope. Not in our lifetimes; or our children’s, probably. Maybe in a few hundred years. Pity I won’t get to see it; it would be so fun to visit Mars.
They can manufacture carbon nanotubes. The hurdle is to finding a way to manufacture them in sufficient quantity at low cost. But they are making real progress! From http://en.wikipedia.org/wiki/Space_elevator:
Shalmanese said:
Of course it depends on the form, but it seems clear that hydrogen and oxygen exists on the moon in at least three forms:
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As cometary residue. This stuff may be eminently mineable. For a while, NASA thought that it might even exist in the form of massive sheets of ice, just waiting to be chipped apart and hauled away. That doesn’t look likely, but it does seem likely from the water signatures lunar prospector and Clementine picked up that it at least exists as ice-rich soil where grains of ice are distributed through the soil in fairly high concentration. After all, the water was detected from orbit, so we’re not talking microscopic amounts.
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In the case of oxygen, bound up in silicates and oxides in the regolith. How hard this is to extract is an open question for me, because I don’t know enough about chemistry.
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In the case of hydrogen, it exists in the regolith as free molecules from the solar wind, from what I understand. So there would be no chemical process required to liberate it - just perhaps some heating, or churning, or whatever it takes to release it.
The ‘gold from water’ analogy doesn’t really hold for a simple reason: Gold is relatively inexpensive compared to the value of water on the moon. We CAN recover gold from seawater, we just can’t do it for less than what the gold would be worth, so we don’t. But if gold were $5000 an ounce instead of $300, I’ll bet we’d find a way.
In any event, we really don’t know what kind of effort we’re looking at right now. We need to go there and explore. Good thing that that’s exactly what NASA is gearing up to do. If extensive water deposits are discovered, it’ll be a huge boost to the prospects of living in space anywhere.