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I read the article twice to be sure, but there was no mention of what ore bodies the Moon has or what their grades are. People are attracted to mining the deep

I read the article twice to be sure, but there was no mention of what ore bodies the Moon has or what their grades are. People are attracted to mining the deep sea because there are seabed nodules and crusts that are enriched in valuable metals like cobalt, nickel, manganese, and copper: https://en.wikipedia.org/wiki/Manganese_nodule https://en.wikipedia.org/wiki/Manganese_nodule "Those of greatest economic interest contain manganese (27–30 wt. %), nickel (1.25–1.5 wt. %), copper (1–1.4 wt. %) and cobalt (0.2–0.25 wt. %)." A nodule containing 1% copper and 1% cobalt is a great ore. These nodules are not found on the moon. As far as we know, no cobalt ore bodies of comparable richness are found on the moon. Transition metal ore bodies on Earth have been formed by Earth's geochemistry, including its hydrological cycle. The Moon does not have liquid water and its minerals are undifferentiated silicates. Undifferentiated silicates are abundant on Earth. Trying to mine them is an exercise in getting $1 of metal from $10 of energy and chemicals. Trying to mine undifferentiated silicates on the Moon means getting $1 of metal from $10 of energy and chemicals plus $10,000 in transportation costs.

adastra22 4y ago
The same metals are available. One of the theories for nodule formation on the seabed floor is that they start from kernels deposited by astroid impacts in the ocean. These same impacts in the moon form craters with more than half of the impactor preserved in the central peak of the crater.
- adrian_b 4y ago
  The main elements that would make sense to be mined from outside the Earth are those which on Earth have gone mostly into the inaccesible core of the planet, e.g. nickel, cobalt, germanium, the platinum-group elements. Such elements are indeed abundant in the iron meteorites, but they have low abundance in the lunar rocks. The lunar rocks have huge quantities of iron, aluminum, titanium, manganese, which would be good for building structures on the Moon, but which are too cheap to be worthwhile to be brought to Earth. I have not seen any estimate for this but I doubt that the total mass of iron meteorites that have fallen on the Moon is great enough to provide a quantity of valuable metals that would be worthwhile to be transported back to Earth. Moreover, the iron meteorites that have fallen on the Moon are distributed uniformly over all it surface, they are not concentrated in some place like the ores on Earth. The cost of transportation until a processing place will be very large, because I doubt that there can be more than a few grams of iron meteorites per square meter. Even with this extremely optimistic supposition, one would need to collect all the meteorites from several hundreds square kilometers to get a ton of cobalt (the average Co content in iron meteorites is a little less than 0.3%). For less abundant elements, like the platinum-group metals, the area will be multiplied by several orders of magnitude. It is unlikely to find places on the surface of the Moon with significantly different chemical composition than other places, because the Moon has neither volcanoes nor flowing water, to create exploitable mineral concentrations. The only chance to find a concentrated source of valuable elements on the Moon would be in the mascons (mass concentrations that are likely to be buried asteroids that have impacted the Moon early in the history of the Solar System), if any of the mascons is close enough to the surface to be reachable by digging. Exploiting a Lunar mascon does not seem easy as their typical burial depth is estimated between 25 km and 125 km. Nevertheless, due to the lower gravity and to the lack of a hot interior, it might be possible to dig much deeper wells on the Moon than on Earth, e.g. maybe to a depth of 20 to 30 km, where some of the mascons could be reached. There is no guarantee that any of the mascons has a metallic core, but the fact that they have a higher density than the Lunar rocks suggests that this is a possibility.
rhodorhoades 4y ago
But why would you ever bring material back to earth that was mined on the moon? Why not just launch it in a earth or cislunar orbit. It’s more valuable there for use in space industry. The moon has a lower delta v to orbit than earth does.

adastra22 4y ago

The same metals are available. One of the theories for nodule formation on the seabed floor is that they start from kernels deposited by astroid impacts in the ocean. These same impacts in the moon form craters with more than half of the impactor preserved in the central peak of the crater.

adrian_b 4y ago
The main elements that would make sense to be mined from outside the Earth are those which on Earth have gone mostly into the inaccesible core of the planet, e.g. nickel, cobalt, germanium, the platinum-group elements. Such elements are indeed abundant in the iron meteorites, but they have low abundance in the lunar rocks. The lunar rocks have huge quantities of iron, aluminum, titanium, manganese, which would be good for building structures on the Moon, but which are too cheap to be worthwhile to be brought to Earth. I have not seen any estimate for this but I doubt that the total mass of iron meteorites that have fallen on the Moon is great enough to provide a quantity of valuable metals that would be worthwhile to be transported back to Earth. Moreover, the iron meteorites that have fallen on the Moon are distributed uniformly over all it surface, they are not concentrated in some place like the ores on Earth. The cost of transportation until a processing place will be very large, because I doubt that there can be more than a few grams of iron meteorites per square meter. Even with this extremely optimistic supposition, one would need to collect all the meteorites from several hundreds square kilometers to get a ton of cobalt (the average Co content in iron meteorites is a little less than 0.3%). For less abundant elements, like the platinum-group metals, the area will be multiplied by several orders of magnitude. It is unlikely to find places on the surface of the Moon with significantly different chemical composition than other places, because the Moon has neither volcanoes nor flowing water, to create exploitable mineral concentrations. The only chance to find a concentrated source of valuable elements on the Moon would be in the mascons (mass concentrations that are likely to be buried asteroids that have impacted the Moon early in the history of the Solar System), if any of the mascons is close enough to the surface to be reachable by digging. Exploiting a Lunar mascon does not seem easy as their typical burial depth is estimated between 25 km and 125 km. Nevertheless, due to the lower gravity and to the lack of a hot interior, it might be possible to dig much deeper wells on the Moon than on Earth, e.g. maybe to a depth of 20 to 30 km, where some of the mascons could be reached. There is no guarantee that any of the mascons has a metallic core, but the fact that they have a higher density than the Lunar rocks suggests that this is a possibility.

rhodorhoades 4y ago

But why would you ever bring material back to earth that was mined on the moon? Why not just launch it in a earth or cislunar orbit. It’s more valuable there for use in space industry. The moon has a lower delta v to orbit than earth does.