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Moon.
Wow,
This is sure a lot of water for place that is not suposed to have any. How many billions of tons of concrete can this make?
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Wow, this strengthens the moon argument. Zubrin won't be happy or maybe he will? ??? I wonder just how much a billion tons of water is. Lets compare it to say a great lake.
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It depends you see there is still no sure way to see how much hydrogen is on the Moon except going and looking.
And the estimate is between 1 million to three billion tons, the leeway is that big. And there is no chance it would be wasted on the very heavy water using construction of concrete. Not when there is other possible and better solutions to providing building materials.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Wow, this strengthens the moon argument. Zubrin won't be happy or maybe he will? I wonder just how much a billion tons of water is. Lets compare it to say a great lake.
I don't know how big the great lakes are, but 1 billion tons(metric)= 1 kilometer^3.
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The by product of making concrete by mixing in a little aluminum is Hydrogen. How much Hydrogen can this much water make using this method?
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The ice was thought to be spread over 10,000 to 50,000 square km (3,600 to 18,000 square miles) of area near the north pole and 5,000 to 20,000 square km (1,800 to 7,200 square miles) around the south pole, but the latest results show the water may be more concentrated in localized areas (roughly 1850 square km, or 650 square miles, at each pole) rather than being spread out over these large regions. The estimated total mass of ice is 6 trillion kg (6.6 billion tons). Uncertainties in the models mean this estimate could be off considerably.
They are still just guessing.
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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There could also be more.
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Also, if any geothermal energy is left there could also be underground water in these regions.
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The by product of making concrete by mixing in a little aluminum is Hydrogen. How much Hydrogen can this much water make using this method?
Answer: Zero, because you can't have stable liquid water on the Lunar surface in order to cure concrete. Nor can you capture the hydrogen that is produced... you'd be throwing it all away.
I never said there was no water, only that there are no frozen ice lakes to exploit: in fact, with that water spread out over hundreds of kilometers it is certainly in the form of a "snow" mixed in with the soil. Do you have any idea how hard it will be extract it efficently? Oh no, no Errorist, water will still be a precious reasource even if it is there.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I don't know how big the great lakes are, but 1 billion tons(metric)= 1 kilometer^3.
When you put it that way it doesn't sound like that much water. At least not what we are use to. Recycle, Recycle, Recycle. No concrete please.
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Answer: Zero, because you can't have stable liquid water on the Lunar surface in order to cure concrete. Nor can you capture the hydrogen that is produced... you'd be throwing it all away.
Answer:Tons and tons of it,because you can create the correct environment for it to cure.Also, when it is curing it warms up a little.
"And you are flat wrong that "huge supply of underground water" will be discoverd... there simply is no way that the Moon ever had water due to its geologic history, and so the only possible source is from comets or other space ice, which would not be deeply buried and probably detected by Aricibo."
Oops, looks like it has been discovered: I guess I wasn't wrong looks like YOU are flat wrong. Ice is water.
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Sure the reaction is exothermic, but exothermic enough to survive the -200 degree cold soak for two weeks? Doubtful, the reaction is so slow that the low temperatures would win out, and it would freeze solid. Not to mention it would take a long time to cure at that temperature even if you could keep it liquid.
Plus the water will vaporize at the surface of the concrete because of the low pressure, which will make the surface crack and break off easily. Then the wet concrete under that will be exposed to space too, and it will dry out and break off... and in the burning hot +200 two-week soak will definatly not help things, since it would cause the concrete to get brittle and make water inside boil and make the concrete crack & shatter.
Ah ha, so you are going to make all your concrete castings indoors huh? So that defeats the cheif advantage of concrete, that you can pour it into place on your building. Guess you can't do that, oh well. Nor can you collect the hydrogen that is made in the reaction. You can't. There is no way to do this on any useful scale, the energy required to operate vacuum pumps would be horrendous plus you can't simply wrap everything you build with meteor-proof/radiation-proof/hydrogen-proof plastic wrap for the months it will take for the stuff to set up.
Errorist, any way you cut it, any way you aproach the problem, the problems are insurmountable... Making concrete on the Moon is simply a horrible horrible idea, and there is no sane way you can support it in light of its many show-stoppers.
Now about that water... ummm Errorist, you are just looking at the big "millions of kilograms!" figure and automatically thinking "water water everywhere!" Well clue in, that really isn't that much water, and would amount to an Earthly lake a little under 100 square kilometers... a pond only like seven miles wide if it were 100m deep.
The smallishness of that figure is such that it proves me correct, that there is no huge underground lake, and that the water is indeed spread out over a pretty big area as ice dust, which cannot be harvested in quantity big enough for you to waste on making concrete. Water will still be a precious commodity, and throwing away all that Hydrogen... the second or third most valuble substance on the Moon... would just be an inconcieveable and insufferable waste.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Well clue in, that really isn't that much water, and would amount to an Earthly lake a little under 100 square kilometers... a pond only like seven miles wide if it were 100m deep.
The smallishness of that figure is such that it proves me correct, that there is no huge underground lake, and that the water is indeed spread out over a pretty big area as ice dust, which cannot be harvested in quantity big enough for you to waste on making concrete. Water will still be a precious commodity, and throwing away all that Hydrogen... the second or third most valuble substance on the Moon... would just be an inconcieveable and insufferable waste.
Wow, that equates to a lake not a pond. It would be at least twice the size of Lake Ockechobee in Florida. To equate this to a pond is a silly comparasion. The right atmosphere for this concrete to form would be easy if it was done underground the temperature could remain a constant 70 degrees by solar energy and the Hydrogen could be collected easy.
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I think this concrete theme is a joke, right? There's no source of calcium carbonate anyway. You'd need to extract calcium oxide from the regolith and add carbon dioxide.
But never mind, I won't continue the concrete theme.
The question in my mind still isn't the quantity, but the ease of extraction. Let us say the south pole has only 1 million tonnes of water, disseminated as 1% by mass frost in 100 million tonnes of regolith, and that the 100 million tonnes is in a deposit 10 meters thick covering 10 million square meters, which is 1,000 square kilometers.
According to an article at the Colorado School of Mines website, 1% frost can be extracted at a reasonable price. No doubt they made a lot of assumptions about technology. But let's say they are right.
A very small lunar operation will need maybe five tonnes of water per person per year for water and oxygen. If you have twenty people on the moon, that's one hundred tonnes per year. Let us say that they need five flights per year from low earth orbit and each flight needs one hundred tonnes of LOX/hydrogen fuel. The moon base therefore uses 600 tonnes of water per year. The million tonnes will last them 1,600 years.
If the base exports water to low earth orbit as one of its economic mainstays, if that export consumes a total of 10,000 tonnes per year for the people, the export, and the fuel to transport the export, the million tonnes would last 100 years. If the operation grew to such a large size, surely in 100 years the technology to haul in water from Phobos, Deimos, or near-Earth asteroids would exist. So it would be economically wise to "use up" the million tonnes in such an operation, because it would bootstrap a much larger operation able to obtain its water elsewhere.
And I suspect there's a lot more than a million tonnes of water at the poles, though that's just a guess. Clearly, IF we can exploit the resource economically (and we will be able to do that eventually), then there will be enough of it there to last a fairly long time; on the same time scale as, for example, the earth's supply of petroleum.
-- RobS
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I like your positive responce Robs. How much water do our astronauts use per day? I think this would be a good guide as to how much a person needs on the Moon per day and what about all that Hydrogen locked up in the water that would make a good propellant for the Vasmir.
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http://www.space-rockets.com/moon1.html]Waterless cement might be used in a manner similar to steel reinforced concrete construction on Earth.
http://science.nasa.gov/newhome/headlin … m]Aerogels could be http://aerospacescholars.jsc.nasa.gov/H … nufactured.
We are likely to get space tourism to the Moon sooner than to Mars, now that all the materials are found there, ready for the ambitious developer, promoter.
A hotel, shopping center, recreational development,
top of a permanently sunlit crater wall would be ideal.
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Marsdog,
All the ingriediants for Mooncrete is there already. Establish a base there first and Mars is right around the corner.
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I am wondering if humans really need 5MT of water a year with recycling, or would that include producing foodstuffs too Rob? Oxygen for breathing could be extracted from the Lunar soil too instead of from water.
I don't know about the idea of hauling Lunar water to Earth orbit though, you are going to need an RLV of very very high reliability, plus could have a hard time competing with Earthly rockets + Ion Tug.
Hmmm so there isn't much in the way of carbon bearing salts in the Lunar soil huh? Well, I guess there won't be any concrete then even if there is water. Too bad... Oh, and the "concrete" mentioned in the article isn't, its a mix of Lunar dirt and plastic/caulking.
"The right atmosphere for this concrete to form would be easy if it was done underground the temperature could remain a constant 70 degrees by solar energy and the Hydrogen could be collected easy."
Well,
1: No its not easy to do "underground" with all the digging involved to make an underground concrete casting foundry.
2: You couldn't ever pour the concrete in place, which is its cheif advantage over simply using Lunar metal.
3: Capturing the Hydrogen is still not practical... you still need big vacuum pumps, hydrogen condensers, and lots and lots of time since it will take so long for it to leach out of the concrete, if ever. Your factory will fill up fast with curing pieces as you try to recycle the hydrogen.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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We can create stronger materials than just using concrete.
As is well suspected there is a lot of sunken metal rich asteroids in the regolith we can use there iron to create super strength structures that will protect our people and machinery. As has been noted a 3 foot thickness of Iron provides the same protection as our atmosphere and on the Moon there will be no rusting.
So why waste this possible incredible source of hydrogen on anything except the improvement of conditions of human occupation. We will create a workforce of telerobotic robots to create what we need reasonably cheaply on the Moon and advance our conquest of space. Yeah I know very prophetic but compared to other choices it gives the most infrastructure to the buck. And if we can do this it allows more done and that is what we are after in the end is it not?
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Refining or even melting down nearly pure metals won't be that easy on the Moon because of the energy demands, so piling up Lunar soil for radiation shielding ought to be the first choice for primary protection, you just scoop it up and carry it.
I think that robots will be helpful for dirt moving and heavy lifting and such, but I have my doubts if they will be ready technologically to build things on their own. Robot dump trucks, bulldozers, and other heavy equipment should be just fine though. Have one operator keep an eye on a team of them (maybe from Earth), and operate them 24/7 and vehicles of small size could move big things given time.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Wow, that equates to a lake not a pond. It would be at least twice the size of Lake Ockechobee in Florida. To equate this to a pond is a silly comparasion.
This is not really relevant to the tread but there may be ponds that big. The difference between a pond and a lake is how fast the water is replaced. There is a very big pond in Newfoundland Canada. Don’t quote me on it but it may be the biggest pond in the world.
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If the base exports water to low earth orbit as one of its economic mainstays, if that export consumes a total of 10,000 tonnes per year for the people, the export, and the fuel to transport the export, the million tonnes would last 100 years. If the operation grew to such a large size, surely in 100 years the technology to haul in water from Phobos, Deimos, or near-Earth asteroids would exist.
If all the savings go into rocket technology I may support this. Phobs and Deimos aside there is also the possibility of shipping hydrogen from earth and reacting it with lunar oxygen. But cheap electric engines would probably give water from Phobos and Deimos and economic advantage even if a space elevator was built.
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That really isn't a lot of water given the area it's actually spread over. It wouldn't even count as a pond in my book, because you're having to process tons of regolith to get at it. Of course, as of now we don't actually have a decent estimate, so that's one reason it's more wise to talk about Mars' water; we have very good models for Mars.
Some useful links while MER are active. [url=http://marsrovers.jpl.nasa.gov/home/index.html]Offical site[/url] [url=http://www.nasa.gov/multimedia/nasatv/MM_NTV_Web.html]NASA TV[/url] [url=http://www.jpl.nasa.gov/mer2004/]JPL MER2004[/url] [url=http://www.spaceflightnow.com/mars/mera/statustextonly.html]Text feed[/url]
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The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.
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The five tonnes of water per astronaut per year estimate was off the top of my head, based on the International Space station, which seems to need quite a few tonnes of water every year. But Zubrin in *The Case for Mars* says that NASA says people need 1 kilogram of oxygen, 0.5 kg dry food, 1 kg whole food, 4 kg potable water, and 26 kg of wash water per day, for a total of 32.5 kg per person per day or about 12,000 kg (12 tonnes) per year. Of course, if one recycles the water that drastically cuts down on the mass. Zubrin assumes recycling of water that is about 90% complete, in which case the astronaut needs 4.3 kg per day (1.57 tonnes per year) of consumables, of which 1.5 kg is food, 0.2 kg is oxygen, and 2.6 kg is water. So that's 949 kg of water per year, not 5 tonnes. If the cycling is even more efficient, then even less is needed.
I agree, it is not clear that export of water to low earth orbit will be economical. It probably will be economical to the L1 Gateway, if such a thing is itself needed and is economic.
As for extracting platinum group metals or utilizing meteoritic nickel-iron, there's a way that is probably cheaper and easier than melting the stuff: blast it with heated carbon monoxide to make metal carbonyls, which are liquids at 100-200C. Each metal forms a complex carbonyl with carbon monoxide. Each carbonyl has it's own temperature where it breaks back down into pure metal and CO gas. One could convert the nickel-iron into iron carbonyl, nickel carbonyl, and cobalt carbonyl, which will eliminate 99% of the mass; the platinum group metals will be concentated in the remaining 1% and will be about 3000 parts per million or 3/10 of 1% of the residue (platinum group metals are about 30 parts per million in typical nickel-iron, meaning 1 tonne has 30 grams of the stuff). The liquid metals could then be poured into mould and heated up to crystalize the carbonyls. The CO would then be recycled. Note that a plant that produced 30 tonnes of platinum-group metals per year (worth about $100 million) would have to process 1 million tonnes of meteoritic material. If the recycling process were 99.9% efficient, the carbon monoxide would be reused 1000 times, and the process would require 1000 tonnes of carbon monoxide to process a million tonnes of meteorite. This is a problem because if carbon is vanishingly rare on the moon, the carbon monoxide would have to be imported. Importation costs right now would far exceed the profits of the platinum-group metals; if platinum-group metals are worth $30 million per tonne (which is about $900 per ounce) and if each tonne of platinum-group metals requires 33 tonnes of CO, importation of CO has to be 30 times less per kilogram than the price of the product, or 1 million per tonne. Right now it costs several times that much to put a tonne into low earth orbit, let alone send it to the moon.
What are the chances of finding carbon on the moon? We know the regolith has vanishingly small amounts of carbon; so small, it would be too expensive to obtain it. Maybe the polar volatiles include carbon dioxide and/or methane, but we simply don't know. Right now the experts seem to doubt there's much of either.
So my guess right now is that lunar production of platinum-group metals will not be profitable. Dennis Wingo's book argues that it will be, but I don't think he dealt with the problem of lack of carbon on the moon. Maybe there are other extraction processes one can use instead.
But this argument also leads one to conclude that Mars is a better place for platinum production, because it has all the carbon one could need. Carbon monoxide can be made from carbon dioxide and it takes maybe 2 kilowatt-hours to make a kilogram of the stuff (plus the 2 kwh is converted to heat, so you can use the heat as well).
-- RobS
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It may be there, but there are issues with the fact that you would have to place your base on the lunar south pole. Also the way I understand it, your still talking about extracting water in PPM concentrations.
This development might make the logisitics of a lunar base seem beter, but I hardly think they significantly alter the balance of power in the Moon vs Mars debate. I still think going to the moon as a preamble to Mars is a very, very ill-logical move that will keep us off mars until the 2050s at least.
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