Helium-3

isotope of helium, non-radioactive

Helium-3 (3He) is a light, stable isotope of helium. It has two protons and one neutron. Helium-3 was discovered in 1939.

Helium-3 occurs as a primordial nuclide. It escapes from the Earth's crust into the atmosphere. It then escape into outer space over millions of years. Helium-3 is also thought to be a natural nucleogenic and cosmogenic nuclide. The amount of helium-3 is thought to be greater on the Moon than on Earth.[1]

References

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  1. "Global inventory of Helium-3 in lunar regoliths estimated by a multi-channel microwave radiometer on the Chang-E 1 lunar satellite". Archived from the original on 2017-10-11.