If you could setup a permanent base on the moon....

[Traab]

Would it be possible to mine materials needed to build things such as space ships up there? Does the moon contain the right mix of mineral content to do that? Do we even know? Also, would mining on the moon be easier, or harder than on earth? Just the act of mining, ignoring difficulty in getting to the moon itself, things like setting up the mines, extracting material, processing it, etc etc etc. What about fuel sources? Obviously there arent going to be vast swathes of oil to frack for, dinosaurs tended to be rare on the moon as far as im aware. But im not sure how efficient things like solar power would be out there, or if they might be able to build batteries up there (im not sure how they are made)

[Tvtyrant]

Pretty sure the Moon has almost no heavy elements, as it was made of surface material ripped off by an impacting planetoid. We only have decent amounts of heavy surface metals because the impact ripped the planet open, otherwise it would have sunk to the bottom when the planet was a liquid.

[Peelee]

Pretty sure the Moon has almost no heavy elements, as it was made of surface material ripped off by an impacting planetoid.

Thays the prevailing theory, but we don't know for certain.

[Telok]

Solar power and nuclear are your lunar energy sources. Solar is great once you put a ring of arrays around a pole to alleviate the lunar night. Nuclear is better than on earth for disposal of waste. You can designate a nice crater and just catapult stuff in. On the other hand it's more problematic since our current large scale power generation via nuclear decay is essentially just using the waste heat to power steam turbines. On the gripping hand you can just run thermocouples or sterling engines off nuclear + a good black body radiator.

Metals are iffy. We don't really know enough about the lunar geology yet. Find the impact site of a large nickel-iron impactor and that could be useful for a while. Mining ice would be really useful though, if there is enough of it. Oxygen and hydrogen in contained reactions are extremely useful up there. With sufficently cheap power extracting them from lunar rock could be feasible.

The big draw is that the Moon is a stable long-term building platform outside of (well, functionally close enough) Earth's gravity well.

[Kaptin Keen]

Someone once told me that the moon is hugely rich in aluminum. I have no idea whether that's right or not.

[Yora]

Almost certainly right. The moon is made of the same material as the surface of the Earth (even with the same isotopic composition, which makes the idea that they have a shared origin extremely likely). And rock on Earth is mostly aluminium-oxide and silicon-oxide.
Not sure how easy it is to separate the two, but aluminium-oxide can be turned into aluminium and carbon-oxide by simply giving it a carbon source and run powerful electricity through it. Question would be where you get the required graphite as a carbon source on the moon.

Another thing the moon has is Helium-3, which people on Earth would really like to get their hands on because it's a great source for fusion energy. If we mine that stuff on the moon to power Earth, it will also be able to power facilities on the moon. Once we have fusion reactors that use less power to run than they produce. We don't know when this will be, but by the time we can talk about aluminium raffineries and shipyards on the moon, I am quite certain that issue will be long solved.

Metals are iffy. We don't really know enough about the lunar geology yet. Find the impact site of a large nickel-iron impactor and that could be useful for a while. Mining ice would be really useful though, if there is enough of it. Oxygen and hydrogen in contained reactions are extremely useful up there. With sufficently cheap power extracting them from lunar rock could be feasible.

One option would be to drag iron-nickel asteroids and carbon asteroids (for aluminium refinement) from the asteroid and drop them on the moon. Iron-nickel asteroids sometimes survive impacts on the Earth intact, so I think on the moon it would be quite easy to just pick them up from where they came down and move them to a refinery. If you have larger ones that don't shatter into smaller fragments, you can just crack them with explosives. Which in the low gravity would be much easier to move than on Earth.

I believe most separation processes of materials rely on lighter ones floating to the top when liquid. And for that you do need gravity. It would take longer in low gravity, but it will eventually happen. If you were to process asteroids in space, your whole refinery would have to be a centrifuge. But I am not sure if that's actually a technical challenge.

[Peelee]

Another thing the moon has is Helium-3, which people on Earth would really like to get their hands on because it's a great source for fusion energy.

IIRC when the movie Moon was screened for NASA, their sole major complaint was that Helium-3 is more abundant on the near side.

[halfeye]

Pretty sure the Moon has almost no heavy elements, as it was made of surface material ripped off by an impacting planetoid. We only have decent amounts of heavy surface metals because the impact ripped the planet open, otherwise it would have sunk to the bottom when the planet was a liquid.

Personally I suspect (I am an amateur in this) that the softer heavy metals at least come to the surface as disolved gases in magma.

I'm pretty sure an impacting planetoid of the size suggested would stir things up all the way to the core, and that almost everything would have been liquid immediately following the impact if it wasn't before.

[Yora]

The mantel of the Earth is really more of a solid than a true liquid, and while over very long time moat heavy material will sink to the core, I think it's quite possible that some traces of them are caught up in the "currents" and dragged to the surface at oceanic ridges.
But the continental crust is more or less floating on top of the oceanic crust, and material that gets shaved off at tectonic subduction zones ends up being deposited at the underside of the crust, which some of it returning to the surface through volcanoes.

Most heavy elements on the continental surface (that's heavier than aluminium and silicon) most likely arrived from asteroid impacts after the surface had already hardened. As the asteroids exploded on impact or in the atmosphere, the material was pulverized and scattered over huge areas and got trapped inside rock as it moved and shifted.
Though I am not sure how different the amounts of other elements are in volcanic and sediment rocks. It should be a lot higher for sediment rocks, I think.

As we can see on the moon, it had a lot of asteroid impacts after its surface hardened as well. There should be similar heavier elements to be found there as there are on Earth. But since it's tectonically inactive and has no sedimentary rock formation caused by water and wind, there wouldn't be any processes that would cause higher concentrations in some places to be easily mined as veins. Everything should still be sitting where it landed.
Useful when you have iron-nickel asteroids that did not break up too much, but probably not so much for many other elements that existed only in trace amounts in rocky asteroids as well.

[factotum]

Realistically, there's not going to be any such thing as a "permanent" moon base until such a base can be self-sufficient on stuff it can mine from the Moon--getting stuff from Earth to Moon is hugely energy-intensive and expensive, which is why we had to build the biggest rocket ever made in order to get 2 people and a few tonnes of equipment to the lunar surface. This means oxygen as well--yes, you can convert some CO2 to oxygen with green flowering plants, but experiments done on the Earth's surface with completely sealed environments full of plants have so far never worked properly.

[DeTess]

Would it be possible to mine materials needed to build things such as space ships up there? Does the moon contain the right mix of mineral content to do that? Do we even know? Also, would mining on the moon be easier, or harder than on earth? Just the act of mining, ignoring difficulty in getting to the moon itself, things like setting up the mines, extracting material, processing it, etc etc etc. What about fuel sources? Obviously there arent going to be vast swathes of oil to frack for, dinosaurs tended to be rare on the moon as far as im aware. But im not sure how efficient things like solar power would be out there, or if they might be able to build batteries up there (im not sure how they are made)

There have been attempts to use (recreations of) lunar dust to create the kind of components you'd need to build and maintain a lunar base with some success: https://www.researchgate.net/publica..._with_moondust

We don't know enough about lunar geology to accurately say things about lunar mining. Regarding energy, solar powers on the lunar surface would generate more power per square meter than on earth because there is no atmosphere to reduce the amount of light coming in. However, the moon also has a very long day-night cycle (about 30 days) which could cause some issues for solar power.

[factotum]

Regarding energy, solar powers on the lunar surface would generate more power per square meter than on earth because there is no atmosphere to reduce the amount of light coming in.

It's not actually a huge difference there--I think you'd get about 50% more power at most from solar panels on the Moon. The long day-night cycle would definitely cause big problems, though, as you say.

[Peelee]

The atmosphere also helps prevent Earthican solar panels from getting hit with rocks.

[halfeye]

The mantel of the Earth is really more of a solid than a true liquid, and while over very long time moat heavy material will sink to the core, I think it's quite possible that some traces of them are caught up in the "currents" and dragged to the surface at oceanic ridges.
But the continental crust is more or less floating on top of the oceanic crust, and material that gets shaved off at tectonic subduction zones ends up being deposited at the underside of the crust, which some of it returning to the surface through volcanoes.

The crust of the Earth is really thin. If you compare it to the skin on the top of a saucepan of liquid food that has just been stirred and is barely simmering, the crust of the Earth is relatively speaking thinner.

Most heavy elements on the continental surface (that's heavier than aluminium and silicon) most likely arrived from asteroid impacts after the surface had already hardened. As the asteroids exploded on impact or in the atmosphere, the material was pulverized and scattered over huge areas and got trapped inside rock as it moved and shifted.
Though I am not sure how different the amounts of other elements are in volcanic and sediment rocks. It should be a lot higher for sediment rocks, I think.

We know (I saw a photo a very long time ago) that gold is sometimes, maybe rarely, released from lava as a gas. If we think about it, gases are typically lighter than their solid or liquid forms, if a gas was dissolved in a liquid (or semi-solid, or whatever you call it at that temperature and pressure) rock it would tend to make that rock lighter than the rock around it so the rock would tend to rise so long as the gas didn't liquify or solidify. This would tend to explain why there is no mother lode of gold to be found, it's distributed though other rocks because it was initially a dissolved gas, not a lump of metal. I'm not that convinced there's a huge cache of gold down in the core, there might be, but it seems to me it ought all to have already become gas and been lifted to the surface.

As we can see on the moon, it had a lot of asteroid impacts after its surface hardened as well. There should be similar heavier elements to be found there as there are on Earth. But since it's tectonically inactive and has no sedimentary rock formation caused by water and wind, there wouldn't be any processes that would cause higher concentrations in some places to be easily mined as veins. Everything should still be sitting where it landed.
Useful when you have iron-nickel asteroids that did not break up too much, but probably not so much for many other elements that existed only in trace amounts in rocky asteroids as well.

It ought to be relatively easy to find impactors, the craters mark them really well.

I think the Moon is a great place to colonise on our way to the rest of the solar system, it's more than halfway out of the Earth's gravity well, and its own gravity well is much less severe. It will still be non-trivial to build there, we will I suspect need to burrow into the rocks. All in all though, it's relatively close and easy to get to, and we know we need to take everything we want with us and we can do that.

[factotum]

We know (I saw a photo a very long time ago) that gold is sometimes, maybe rarely, released from lava as a gas.

Citation needed? The boiling point of gold is 2970K, which is hotter than even deep magma, much less lava near the surface (which is typically much cooler).

[Traab]

Realistically, there's not going to be any such thing as a "permanent" moon base until such a base can be self-sufficient on stuff it can mine from the Moon--getting stuff from Earth to Moon is hugely energy-intensive and expensive, which is why we had to build the biggest rocket ever made in order to get 2 people and a few tonnes of equipment to the lunar surface. This means oxygen as well--yes, you can convert some CO2 to oxygen with green flowering plants, but experiments done on the Earth's surface with completely sealed environments full of plants have so far never worked properly.

That was honestly what I was asking about, can we make a self sufficient moon base that can be used for further exploration of space by being able to build its own stuff? Leaving earth is a massive PITA but if we can reach the moon and setup shop there, further hops would be much much easier. IF and only if, you could create the needed industry up there rather than having to constantly send supplies from earth which defeats the whole purpose. And one of the biggest factors there is if the needed minerals and such can even be found there. As an alternative, using it as a truck stop. Basically, we build the ship on earth, but figure out a way to refuel it on the moon for its next flight out. But again, that would depend on having a fuel source the ship can use that can be harvested on the moon.

[halfeye]

Citation needed? The boiling point of gold is 2970K, which is hotter than even deep magma, much less lava near the surface (which is typically much cooler).

Hm, I thought I answered this, not well perhaps, but as good an answer as I have to give.

A very long time ago, I saw a photo of a tiny plant next to a lavaflow, and it was being covered with a thin (presumably microscopically thin since it wasn't drying out or catching fire) layer of shiny yellow metal which was said in the caption to be gold (I suppose it could have been faked with gold paint, but it was before computers so it wasn't exactly Photoshoped). The photo was in a magazine, which might have been a National Geographic, but I'm not sure of that, it might also have been a sunday supplement with a national newspaper, because in those days there was only the National Geographic as a stand alone picture magazine.

That was honestly what I was asking about, can we make a self sufficient moon base that can be used for further exploration of space by being able to build its own stuff? Leaving earth is a massive PITA but if we can reach the moon and setup shop there, further hops would be much much easier. IF and only if, you could create the needed industry up there rather than having to constantly send supplies from earth which defeats the whole purpose. And one of the biggest factors there is if the needed minerals and such can even be found there. As an alternative, using it as a truck stop. Basically, we build the ship on earth, but figure out a way to refuel it on the moon for its next flight out. But again, that would depend on having a fuel source the ship can use that can be harvested on the moon.

While I get what you are saying, I think there is a case for a forward base or beachhead even if it produces nothing itself. I suspect there are things that can be produced on the moon, the collection of solar energy or water from polar craters for two, but I'd want us to be there even if there was no possibility of those for a while. In the short term, any moon base is going to be an expense, even if it turns out to be profitable in the longer term. So long as everything is recycled properly (which we don't do down here because we don't really need to and there's always a profit to be made on skimping), then I think a moonbase could be fairly selfcontained even if it was a cost to set up that would possibly never be recovered.

[Tyrant]

While I get what you are saying, I think there is a case for a forward base or beachhead even if it produces nothing itself. I suspect there are things that can be produced on the moon, the collection of solar energy or water from polar craters for two, but I'd want us to be there even if there was no possibility of those for a while. In the short term, any moon base is going to be an expense, even if it turns out to be profitable in the longer term. So long as everything is recycled properly (which we don't do down here because we don't really need to and there's always a profit to be made on skimping), then I think a moonbase could be fairly selfcontained even if it was a cost to set up that would possibly never be recovered.

My question after reading Traab's post was going to be related to this. Even if the moon base can't produce much/anything on it's own, would it still have value as a collection point of sorts for parts being sent into orbit to build spacecraft that would have difficulty leaving Earth's atmosphere once fully constructed? It would be expensive, to be sure. But would it better allow us to build larger spacecraft? With the obvious follow up of do we want to build larger spacecraft? And could it eventually serve as some kind of midway between Earth and those spacecraft? That way they don't have to have parts of themselves entering and leaving Earth's atmosphere and instead having people and materials transfer on the moon. Would any of this help an eventual goal of setting up a permanent presence on Mars?

The only book I have ever read that touched on the subject was a book that was trying to detail how to viably get missions to Mars going. The author felt returning to the moon was mostly pointless due to lack of resources. From what I have followed in the occasional news story, NASA feels it is a good idea to go back to the moon before we go to Mars as a testing ground of sorts and to relearn anything that may have been lost since we last went to the moon.

[halfeye]

The only book I have ever read that touched on the subject was a book that was trying to detail how to viably get missions to Mars going. The author felt returning to the moon was mostly pointless due to lack of resources.

I would say the same things about Mars. Mars is a lot harder to get to, once you go down it's a lot harder to get back to Mars orbit and then a lot longer to get home, but that's the only significant difference.

From what I have followed in the occasional news story, NASA feels it is a good idea to go back to the moon before we go to Mars as a testing ground of sorts and to relearn anything that may have been lost since we last went to the moon.

Going to the Moon is difficult enough to be a challenge, but not so difficult that we ought to lose anybody without making serious mistakes. Mars is much harder, people will die if we go there in the short term. We should go to the whole solar system eventually, and Mars is a part of that, but so is establishing a firm beachhead on the Moon first.

[factotum]

I'm not sure that building spacecraft on the Moon makes a huge amount of sense--there's still a gravity well there, even though it's much weaker than Earth's. Surely building in orbit, as was done with the International Space Station, would be the way to go if building a long duration spaceship?

[Telok]

I'm not sure that building spacecraft on the Moon makes a huge amount of sense--there's still a gravity well there, even though it's much weaker than Earth's. Surely building in orbit, as was done with the International Space Station, would be the way to go if building a long duration spaceship?

For spaceship construction you'll generally want a nice, empty, high orbit. You could build landers and probes on the Moon though.

What a Moon base would be good for is any resource extraction possible, food & water & recycling, and a nice stable storage spot where the reaction mass from your workers maneuver thrusters won't affect your supplies and set them spinning or wandering off.

[Tyrant]

I would say the same things about Mars. Mars is a lot harder to get to, once you go down it's a lot harder to get back to Mars orbit and then a lot longer to get home, but that's the only significant difference.

If I recall correctly, the author was arguing that Mars could be more hospitable and that we would gain more from a prolonged stay (building a base, ultimately). Essentially, Mars has an atmosphere which the moon does not and Mars is more distant from the sun which combines to mean less radiation reaches the surface of Mars than reaches the surface of the moon. Though he did concede that it might still be necessary to build the base underground to totally shield from the radiation. I do not recall what resources he said were present. I believe he went into the idea of bring asteroids into near Mars orbit to mine them. It's been a while since I read the book and I may be conflating that with another book or discussion on the topic.

His overall argument/plan involved something similar to what we see in The Martian. NASA would send unmanned missions meant to supply the later, manned missions. Each mission would add to the resources on the planet that would be pooled to construct a more permanent facility, eventually. He argued against using an overly large spacecraft (in his words, the Battlestar Galactica) because it would just become a budgetary boondoggle that would drive up the cost as everyone at NASA that has a project that can be even remotely attached to it would argue to do so to get funding.

Digging around a little, here is the book. I didn't realize it was written in 1996 so some of it might be dated now.

[factotum]

His overall argument/plan involved something similar to what we see in The Martian. NASA would send unmanned missions meant to supply the later, manned missions.

I recall watching a movie that was made before the actual moon landings, but talking about a theoretical future moon landing, in which they sent several unmanned supply depots to the Moon first, and the actual manned mission was aimed to land at one. (In the end the guy landed without having seen a supply base, and managed to stumble across one via luck).

[halfeye]

I recall watching a movie that was made before the actual moon landings, but talking about a theoretical future moon landing, in which they sent several unmanned supply depots to the Moon first, and the actual manned mission was aimed to land at one. (In the end the guy landed without having seen a supply base, and managed to stumble across one via luck).

Talk about billions to one against, but that's the film industry for you, statistics are totally always lies in films.

[Gnoman]

In theory, orbiting anything from the moon would be far easier than doing so on Earth or Mars, due to the lack of atmosphere and lower gravity. Not only would rockets benefit, but you'd probably have an easier time using alternative launch methods - tank cannon already routinely reach 1.7 km/s, and the Lunar escape velocity is 2.38. There are plausible arguments that the moon would be an ideal collection point for asteroid resources - you bring the asteroid (or chunks thereof) into Lunar orbit and deorbit, gaining you much easier access to the goods within (having any gravity at all would make things easier in a lot of ways). This would be more convenient than trying to mine directly from asteroids, without incurring the risk of directly smacking Earth with a big chunk of space rock - since any colony on the moon would pretty much have to be sublunar, smacking the moon wouldn't be a big deal. Then you refine and process the asteroid materials and either ship them to Earth under controlled conditions, use them for lunar infrastructure, or build modules for a fleet to exploit the system.


The big obstacle is not so much lunar resources (once you get asteroid mining going, there's a good chance you'd get enough ice to provide water and oxygen), but the low lunar gravity. The longest anybody's stayed in orbit was 14 months - the cosmonaut in question appears to have suffered no permanent impairment, but we don't know if that would hold true for a two or three year stay in lunar gravity - let alone a permanent one.

[factotum]

The big obstacle is not so much lunar resources (once you get asteroid mining going, there's a good chance you'd get enough ice to provide water and oxygen), but the low lunar gravity.

If you're mining asteroids for resources, why would you fire those down into the Moon's gravity well so you have to waste fuel lifting them back out again? Some sort of rotating base (to provide artificial gravity) would be a far better place to use for such things, and you could arrange for that to have a much higher gravity than the 1/6g the Moon has. And note that we already know how to build such a thing from a structural point of view because it's essentially a suspension bridge with the two ends connected together in a loop--it doesn't require anything too exotic.

[Yora]

Ultimately space stations are te only way to stay long term anywhere but on Earth. But people just want to stand on other planets like their childhood sci-fi fantasies.
Perhaps habitats on the Moon and Mars will be hotels for tourists, with all the industrial stuff staying up in space where it belongs.

[Altair_the_Vexed]

IIRC when the movie Moon was screened for NASA, their sole major complaint was that Helium-3 is more abundant on the near side.

But if you're going to strip mine the Moon, it's easier to get permission to do it on the far side. No-one down here wants look up at the most conspicuous and romantic of heavenly bodies and see it all scarred up by mining operations!

[halfeye]

If you're mining asteroids for resources, why would you fire those down into the Moon's gravity well so you have to waste fuel lifting them back out again? Some sort of rotating base (to provide artificial gravity) would be a far better place to use for such things, and you could arrange for that to have a much higher gravity than the 1/6g the Moon has. And note that we already know how to build such a thing from a structural point of view because it's essentially a suspension bridge with the two ends connected together in a loop--it doesn't require anything too exotic.

We've messed up suspension bridges a time or two. The thing about moon bases is they can be modular, a suspension bridge is dependent on its whole structure all the way along, any big failure wrecks the whole thing.

I am deeply sympathetic to the "don't go back into gravity wells" idea, but I don't feel the Moon's gravity well is problematically deep.

[Peelee]

But if you're going to strip mine the Moon, it's easier to get permission to do it on the far side. No-one down here wants look up at the most conspicuous and romantic of heavenly bodies and see it all scarred up by mining operations!

Get permission from who?

Also, the moon is big. Like, it's a lot smaller than the earth, but it's still very, very, very big.