The moon has 3He, at a concentration of maybe 10ppb, in regolith the heating of which would use more energy than the released 3He would yield in fusion.
Helium at cosmic isotope ratios is 120ppm 3He. So if there were a planet out there with an atmosphere of this helium, extracting the 3He would be much easier (just compress, liquefy and separate, which you'd have to do with lunar helium anyway.)
Helium at cosmic isotope ratios is 120ppm 3He. So if there were a planet out there with an atmosphere of this helium, extracting the 3He would be much easier (just compress, liquefy and separate, which you'd have to do with lunar helium anyway.)