Lunar regolith seems to be about 20% silicon (by mass).
We could try to lift that much silicon from earth's gravity well, or try to build a refinery and launch system on the moon, with ~1/6th the gravity of earth.
There's basically zero carbon on the moon. A ton of it on Mars though (lots of CO2 ice).
Our moon is something like 45% silica on the surface. That is a fuckton of silicon. Step one is definitely making a solar panel factory, and then using that power to smelt aluminum, iron, titanium, etc. It seems to me that the moon would make for a good floating semiconductor fab, and eventually, data center. It would be great for making large structures for spacecraft, since the materials are right, and the lower gravity makes it much cheaper to get the parts into space.
It doesn't make sense for a ton of people to live there, since we would have to bring all of our own carbon, which is kind of important for biological life.
On the other hand this is about 0.1 sqkm of lunar surface stripped and processed. This feels like a pretty small quarry mine on earth. Given that, it feels like it would probably be worth shipping the materials one would need to operate a quarry plus build the ISRU as without material environmental concerns you could process considerably more in a sustainable fashion than shipping elements from earth. The ISRU could extract all sorts of other useful materials -
Oxygen
Silicon (can be used to make plastics)
Iron
Aluminum
Magnesium
Sodium
Potassium
Phosphorus
Etc
Power would be abundant to fuel the reactions via solar radiation. So I wouldn’t write it off, I think regolith processing would be foundational for establishing any meaningful presence. Likely it can be entirely automated as well.
For silicon based things, the moon would make sense for manufacturers. Is there enough solar energy for something like that? Specifically for smelting and refinement? What materials would need to be shipped in for manufacture?
Wow you're right! Its apparently a huge thing on the moon:
"Aluminum composes 10% of the atoms and 13% of the mass of lunar highland regolith, being the third most abundant element. In the mare basins, aluminum makes up only 4.5% of the atoms and 5% of the weight, strongly suggesting the use of highland feedstocks for aluminum extraction."
Pretty much a little solar energy and a crucible and you'd turn out aluminum like mad. Absolutely the right choice for a lunar civilization, instead of lifting structures from Earth's gravity well.
There's abundant calcium, silicon, aluminum, titanium and oxygen on the moon. You bring in hydrogen and export tritium and a lot of the rest could be used to expand settlements and build up space infrastructure.
Dirt is abundant near every solid surface. Not sure it's a valuable commodity but regolith glass would be more interesting. I'm curious about the metallurgical processes we can do easily on the moon.
What do you mine on the Moon? Moon's gravity may be 1/6th that of Earth's - but that is still a lot to overcome to bring back anything substantial. I keep hearing about Helium3 fusion. But we don't have any commercially viable fusion reactors around. There may be water - but it's likely going to take a lot of processing to extract. What else is there that we can't get on this planet and is worth the cost of lifting from the Moon?
Shipping costs from the moon to anywhere on earth is probably pretty minimal, since you could do it with a catapult and a shell+parachute so the goods survive re-entry. I doubt mass would make a big difference there so much as volume.
Shipping costs from earth to the moon is $10 000/KG IIRC though, which, if we assume that a processor weighs 10 grams and costs $100 means the value of the stuff you're selling is $10 000/KG, i.e. you can't make a profit on them.
But, suppose you ship 50% of the processor's materials up (with a convenient 100% efficiency of raw materials usage), and you mine the other 50% locally. Which, does the moon have silicon? Yes, it has plenty. https://en.wikipedia.org/wiki/Lunar_resources#Resources
I suspect lunar silicon would be more expensive to process than terran silicon, primarily due to the lacking skilled labour market in the area. It would likely need to be extensively automated, and likely re-invented from the ground up around the different atmosphere (which while not breathable, is possibly still not clean enough for a cleanroom), gravity, potential power sources (metallurgical coal is a no-go, mainly because there's no easy oxygen but also because coal is quite expensive there).
While it's possible that some raw materials are cheaper on the moon than elsewhere (e.g. platinum from asteroids), I doubt this is the case due to the previously mentioned potential for cheap moon-to-earth shipping.
So 70,000 tons of regolith? I'm not a moon engineer or anything, but I think given the choice of bringing 70 tons of nitrogen, or the equipment to process that amount of regolith over a reasonable scale you'd just bring the nitrogen.
Lots of progress, still clearly many improvements possible. Baby steps!
This could be very useful in a lunar colony, quickly smelting parts and structures out of the lunar soil. It's around 8% aluminum (bauxite) which melts at a reasonable temperature. Strong enough for larger-scale building uses such as airlocks and beams.
The Moon has abundant iron and aluminium. Carbon and hydrogen are possibly an issue but capture a comet or two and that problem goes away. I'm not sure what the state of phosphorus is but luckily we don't need all that much of it.
What would we need from Earth? What would be economical to ship from Earth?
Moon is close by, has plenty of sunlight, aluminum and apparently iron ores, some water. It all is at a reasonable gravity that allows to safety operate on the surface, but cheaply launch a lot into earth orbit, even using electromagnetic catapults that don't require a propellant.
The flow of mass would be the other way around. Lunar regolith has every element embedded in it and there’s little need to bring anything but bootstrapping -to- the moon. Return to earth from the moon wouldn’t be CO2 producing anywhere but the moon.
In addition to selenology (which is a big deal because no celestial bodies other than Earth are so far extensively explored) and places for telescopes, Moon can be a source of some metals (Al, Ti, Fe), oxygen and some other elements, perhaps hydrogen. By mass metals and LOX/LH2 could be the majority of mass transported in Moon-Earth space in near future. Other important payloads are electronics - relatively light - and humans.
So Moon can supply vast majority of material needed for operations in Moon-Earth space. You can maybe launch the materials using a mass driver (some demos here - http://ssi.org/mass-driver-demonstration-tapes/), but even more conventional technology will give you results.
We could try to lift that much silicon from earth's gravity well, or try to build a refinery and launch system on the moon, with ~1/6th the gravity of earth.
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