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What is the most attractive resource available to be extracted on the Moon?

By the most attractive I mean the most useful considering the location in which it's extracted and including all the related extraction and exploitation costs. For instance a resource that is only useful once brought back to earth should factor in all the costs related to shipping back to earth the material.

Rexcirus
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    antique spaceflight memorabilia – uhoh Mar 03 '23 at 11:12
  • Are you limiting this to current or expected near-term costs (say 50 years)? As mentioned in one of the answers there may be no attractive resources in the foreseeable future based on this criteria. Your question probably makes the assumption that extraction and shipping material to Earth will at some time in the indeterminate future become practical, however that's not exactly a given so you may want to add that qualifier to the question. – Steve Pemberton Sep 12 '23 at 12:09
  • Yes, limiting to expected near-term costs, e.g. 30-50 years, is in the spirit of the question. As an entrepreneur I want to target low-hanging fruits in terms of ROI. You are correct in saying that even the most attractive resource may not be attractive currently in absolute terms, but that may change given some innovations or wider business plans. – Rexcirus Sep 12 '23 at 12:29

4 Answers4

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First off almost all resource extraction in space is really only remotely close to cost effective if the resources themselves are used in space.

The general number thrown around is ~$10,000 per pound to low earth orbit, the price goes up if you want it further out. With the high costs even very high priced materials (diamonds, gold, helium isotopes or other unobtaniums) are not likely to generate a positive return considering the very high costs of delivering extraction equipment and returning the materials, but items that can be used in space will benefits in comparison because of these high launch costs when they are competing with the same materials launched from Earth.

Now with that out of the way, what can we get from the moon, that you would need in space.

  1. Water - Lunar water is very useful because it can be used directly by humans, but mosly because it can be broken down into hydrogen and oxygen and used for propulsion.

  2. Oxygen - The biggest makeup of lunar regolith is oxygen (present as oxidized minerals). This oxygen is very useful, not only for life support for humans, but again as an oxidizer for your rocket propulsion.

A Chart

  1. Other Structural Metals - If you want to construct anything sizable in space it gets very expensive to send all that material from Earth, at some point it would be less expensive to send the extraction and processing equipment to provide material from space to save on launch costs. Iron, Aluminum, Magnesium, or Calcium* are available in abundance on the moon.
    *Calcium is a very reactive metal not used on Earth due to its rapid oxidation, but it might be useful for constructions in a vacuum
Josh King
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    Nice answer. What about Helium-3? – Rexcirus Aug 10 '18 at 13:57
  • @Rexcirus Fusion Energy is still around 7 years out and although helium-3 is rare on Earth, there's lots of other fuels that a fusion reactor can use. For example, one approach uses helium-4 which can be generated by lining the walls of the reactor with lithium. By the time where we could use Moon helium-3 I'd expect other reactors to be so far ahead technology-wise that using it would be a step backwards. Also, mining it wouldn't be a walk in the park. You'd have to scrape the upper layer of regolith on the moon over vast swashes of land to collect even a tiny amount. – Dragongeek Aug 10 '18 at 15:43
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    @Rexcirus: We will be able to produce helium-3 at large scales by breeding excess tritium with D-T fusion long before we can actually burn helium-3 in a reactor to produce energy. For that matter, we can produce helium-3 now with fission reactors. And if you can do helium-3 fusion, you can do p-B11 fusion for the same benefits, but without the need for an exotic fuel. Spending the next couple centuries scouring the entire surface of the moon for fusion fuel is a pretty poorly thought out approach to providing Earth's energy needs. – Christopher James Huff Aug 12 '18 at 18:40
  • @Josh King: On the matter of calcium, note that per unit mass it's a better electrical conductor than copper: about double the resistivity, but less than 1/5th the density. Calcium wires would need to be thicker, but they'd be lighter. It just corrodes rapidly on exposure to air down here on Earth. – Christopher James Huff Aug 12 '18 at 18:49
  • @ChristopherJamesHuff Aluminum is better in conductivity per weight than copper and it may exposed to air. – Uwe Aug 25 '19 at 11:54
  • @Dragongeek - how'd you pick 7 years? I'd have said 50. (as in, it's 50 years out, just like it's been for the last 50 years) – codeMonkey Mar 08 '23 at 18:28
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    @codeMonkey in two years (2025), the ITER project is scheduled to achieve first fusion. Granted, this is still an experimental reactor and likely won't ever contribute to France's electrical grid, but I think it's definitely coming. Lots of people are working on the subject, and while it might take another 50 years until a fusion powerplant is powering your house specifically, I think the age old "fusion power is always 20 years away" meme is going to slowly die over the next couple decades as well-funded and ambitious projects come to fruition and interest builds. – Dragongeek Mar 11 '23 at 14:02
  • @Dragongeek The NIF (National Ignition facility) https://en.m.wikipedia.org/wiki/National_Ignition_Facility achieved fusion with getting more out than put in. They said they got 1.5x the amount out of it than they put in!! That is a real breakthrough! – The Rocket fan Sep 07 '23 at 08:35
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    @TheRocketfan - The NIF results got quite a lot of attention last year but turned out to be a bit overblown. What actually happened was that 400 megajoules of power was used to charge a laser, the laser then zapped a tiny container with 2 MJ of ultraviolet light, the implosion released 3 MJ of energy. So 400:3. This research is only related to quality assurance of nuclear weapons, it is not a method that is feasible for power production. The 1.5 to 1 result was an incremental improvement in their methods, not really a breakthrough in the "turning the corner" sense that we normally think of it. – Steve Pemberton Sep 12 '23 at 11:02
  • @StevePemberton you do have a point that they did need 400 joules to power the lasers, however fusion technologies have made some major progress lately. – The Rocket fan Sep 12 '23 at 11:22
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Lunar ice may be of some importance for a different reason: its possible role in making iron and steel.

On Earth, we commonly use carbon (coke) to smelt iron from its oxides, thus to make steel. But coal deposits are not known on the Moon. Therefore hydrogen obtained from electrolysis of water would be a more attractive reducing agent (reduction of iron oxides by hydrogen is also gaining traction in Earth, as a means of reducing carbon footprint). Lunar ice also contains carbon itself, which can be used for either reduction or as a constituent in the steel:

Carbon is present in carbon-bearing ices at the lunar poles in concentrations as high as 20% by weight. However, most carbon-bearing ices have a 0-3% by weight carbon concentration.

Unoxidized, native iron is also more common on the Moon than on Earth.

Oscar Lanzi
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At this stage, I believe the most attractive resource should be titanium iron ore (Ilmenite.) Firstly, it can be used to obtain water resources through hydrogen reduction. Secondly, it provides metal resources such as iron and titanium. However, the titanium iron ore content is relatively low. Effectively enriching titanium iron ore is a challenge that needs to be addressed in the future.

JCRM
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    Welcome to Space SE! At the moment your answer does not actually mention the concentration of Titanium in lunar soil, which would improve it (ideally linking a source). It might also help to explain where the hydrogen for the reduction process is coming from, since it is fairly rare on the moon. – GremlinWranger Sep 07 '23 at 07:57
  • Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center. – Community Sep 07 '23 at 08:21
  • Hydrogen is rare on the moon compared to Earth, but it receives a regular supply,

    It was found in the Apollo samples (equatorial-ish), found in greater concentrations by Chang-e5 in the mid-latitudes, and Chandrayaan-3 will be looking for it in the polar regions.

    – JCRM Sep 13 '23 at 08:17
  • What "regular supply"? The solar wind? If captured at 100% efficiency, the solar wind would supply about a hundred grams per square kilometer per year. Hydrogen may have been detected, that doesn't mean it's available in sufficient quantities to be a useful resource. – Christopher James Huff Sep 23 '23 at 13:17
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The most attractive resource on the moon will be the one that most reduces the costs to taxpayers of proposed moon missions. Water seems the most likely candidate.

Any mining on the moon must contend with extreme pre-investment and operating costs that bear no real relationship to commodity prices. There is no prospect of viable mining to service commodity market demands or that can induce self-perpetuating commercial investment; transport costs alone are probably thousands of times too high for commercial viability.

Ultimately there is no separate moon economy and the primary attraction of in-situ resource utilisation is reducing costs to taxpayers of moon bases that have no commercial basis. As a cost reduction a thousand liters of water on the moon could be "valued" at many millions of US dollars but the on-Earth and on-moon pre-investments needed to deliver that thousand litres is difficult to quantify.

I think we can assume it would be an extraordinarily expensive undertaking, made more difficult for being unable to utilize any regular mining equipment that is mass manufactured as well as the extreme difficulties of sending heavy machinery to such a distant and extreme location.

We cannot know what it will cost or even how without doing it.

Ken Fabian
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    Is there an actual answer here to "What is the most attractive resource available to be extracted on the Moon? By the most attractive I mean the most useful considering the location in which it's extracted and including all the related extraction and exploitation costs" or is this an explanation why you feel the question should not have been asked? – uhoh Sep 12 '23 at 03:02
  • It seems that your answer to the question about "most attractive resource" is that when you "factor in all the costs related to shipping back to earth the material" that there are no attractive resources. I think that is an interesting and probably a valid point of view, however it is essentially challenging the premise of the question, so it would normally be posted as a comment. If you are posting it as an answer I think it would help if you more clearly relate it to specific parts of the question. What you wrote implies this, but I think it would help if this was stated more explicitly. – Steve Pemberton Sep 12 '23 at 11:58
  • Fair points. I don't think mining the moon offers any resources that are attractive to mine the way mineral resources on Earth are but I have edited to include a more direct answer to the question asked. – Ken Fabian Sep 13 '23 at 02:37