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I've heard that the real resource is the heavy hydrogen contained in the first millimeters of the crust as a result of the bombardment of solar winds. If we co

I've heard that the real resource is the heavy hydrogen contained in the first millimeters of the crust as a result of the bombardment of solar winds. If we could use it for fusion power, the heavy hydrogen contained on the moon would power the world nearly forever.

username223 8y ago
> If we could use it for fusion power... That's a big if: http://www.newyorker.com/magazine/2014/03/03/a-star-in-a-bottle http://www.newyorker.com/magazine/2014/03/03/a-star-in-a-bot... I don't expect to see a practical fusion reactor on Earth within my lifetime, much less on the moon. Just imagine the cost of building a Tokamak there.
- hsnewman 8y ago
  I think the plan is to mine the crust and bring it to the earth for fusion.
  - username223 8y ago
    That seems like a lot of work to get deuterium and tritium on Earth. If mining them from the moon is really the cheapest option, I am even less optimistic about fusion.
    - mLuby 8y ago
      It's a lot of work to set up the operation (any extraterrestrial endeavor is) but once there it should be possible to launch canisters of fusion fuel back to earth cheaply using some of that fuel for power, a railgun, and the fact that the Moon is tidally locked to the Earth. Could easily be cheaper than sifting through huge quantities of seawater for the right isotopes.
thinkcontext 8y ago
I believe you are thinking of light helium (helium-3), not heavy hydrogen. Everything I've read about mining on the moon mentions it. Heavy hydrogen, deuterium, is (relatively) abundant on earth and can be harvested from seawater. Heavier hydrogen, tritium, is quite rare, on earth its produced by bombarding lithium. It has a half life of 12 years so it wouldn't be accumulate to useful amounts on the moon. It does decay into helium-3 which is stable, that's why it does accumulate. Fusion with helium-3 takes place at a much higher temperature than deuterium / tritium (DT) fusion, that makes the confinement problem more difficult than the much more studied DT pathway to fusion power generation. One advantage is the possibility of direct conversion to electricity. All this is discussed in https://en.wikipedia.org/wiki/Helium-3 https://en.wikipedia.org/wiki/Helium-3

username223 8y ago

> If we could use it for fusion power... That's a big if: http://www.newyorker.com/magazine/2014/03/03/a-star-in-a-bottle http://www.newyorker.com/magazine/2014/03/03/a-star-in-a-bot... I don't expect to see a practical fusion reactor on Earth within my lifetime, much less on the moon. Just imagine the cost of building a Tokamak there.

hsnewman 8y ago
I think the plan is to mine the crust and bring it to the earth for fusion.
- username223 8y ago
  That seems like a lot of work to get deuterium and tritium on Earth. If mining them from the moon is really the cheapest option, I am even less optimistic about fusion.
  - mLuby 8y ago
    It's a lot of work to set up the operation (any extraterrestrial endeavor is) but once there it should be possible to launch canisters of fusion fuel back to earth cheaply using some of that fuel for power, a railgun, and the fact that the Moon is tidally locked to the Earth. Could easily be cheaper than sifting through huge quantities of seawater for the right isotopes.

thinkcontext 8y ago

I believe you are thinking of light helium (helium-3), not heavy hydrogen. Everything I've read about mining on the moon mentions it. Heavy hydrogen, deuterium, is (relatively) abundant on earth and can be harvested from seawater. Heavier hydrogen, tritium, is quite rare, on earth its produced by bombarding lithium. It has a half life of 12 years so it wouldn't be accumulate to useful amounts on the moon. It does decay into helium-3 which is stable, that's why it does accumulate. Fusion with helium-3 takes place at a much higher temperature than deuterium / tritium (DT) fusion, that makes the confinement problem more difficult than the much more studied DT pathway to fusion power generation. One advantage is the possibility of direct conversion to electricity. All this is discussed in https://en.wikipedia.org/wiki/Helium-3 https://en.wikipedia.org/wiki/Helium-3