The Moon's surface contains helium-3 at concentrations on the order of 0.01 ppm. A number of people, starting with Gerald Kulcinski in 1986, have proposed to explore the moon, mine lunar regolith and using the helium-3 for fusion. Because of the low concentrations of helium-3, any mining equipment would need to process large amounts of regolith, and some proposals have suggested that helium-3 extraction be piggybacked onto a larger mining and development operation.
Cosmochemist and geochemist Ouyang Ziyuan from the Chinese Academy of Sciences who is now in charge of the Chinese Lunar Exploration Program has already stated on many occasions that one of the main goals of the program would be the mining of helium-3, from where "each year three space shuttle missions could bring enough fuel for all human beings across the world."
In January 2006 the Russian space company RKK Energiya announced that it considers lunar helium-3 a potential economic resource to be mined by 2020, if funding can be found.
Mining gas giants for Helium-3 has also been proposed. The British Interplanetary Society's hypothetical Project Daedalus interstellar probe design was fueled by Helium-3 mines on the planet Jupiter, for example. Jupiter's high gravity makes this a less energetically favorable operation than extracting Helium-3 from the other gas giants of the solar system, however.
