Helium‑3 is a rare, stable isotope of helium with two protons and one neutron, first isolated in 1939 after being proposed by physicist Mark Oliphant in 1934. Unlike the more common helium‑4, it is fermionic and exhibits unique quantum properties such as becoming a superfluid at extremely low temperatures. On Earth, helium‑3 is scarce, occurring in trace amounts in the atmosphere, mantle, and natural gas deposits, and is mainly produced through the radioactive decay of tritium. However, it is thought to be more abundant on the Moon, where solar wind has implanted it into the regolith over billions of years, and in the atmospheres of gas giants. Its potential as a clean nuclear fusion fuel—because helium‑3 fusion reactions produce little to no harmful neutron radiation—has made it a subject of scientific and geopolitical interest, though practical extraction and use remain technologically and economically challenging
The new mineral discovered on the Moon, named Changesite- (Y), was identified by Chinese scientists from lunar samples collected during the Chang'e-5 mission. This mineral is a phosphate with a chemical formula of (Ca8Y)□Fe2+ (PO4)7, forming colorless, transparent columnar crystals in basalt particles. It was first identified by researchers at the Beijing Research Institute of Uranium Geology and is the sixth new lunar mineral to be found. Changesite- (Y) is significant as it contains helium-3, a rare isotope that could be used in nuclear fusion, potentially providing a clean energy source for future generations.
Timeline of Helium‑3
1934 – Australian physicist Mark Oliphant first proposed the existence of Helium‑3 while experimenting with nuclear reactions at Cambridge’s Cavendish Laboratory.
1939 – Luis Alvarez and Robert Cornog successfully isolated Helium‑3, proving it was a stable isotope rather than radioactive.
1972 – Researchers published the discovery of superfluid Helium‑3, showing that unlike bosonic Helium‑4, it behaves as a fermion and enters a superfluid state at millikelvin temperatures.
Late 20th Century – Helium‑3 became recognized as a byproduct of tritium decay in nuclear reactors, making it available in small industrial quantities.
2000s–Present – Interest grew in Helium‑3 as a potential fusion fuel due to its aneutronic reactions (producing little radioactive waste). Scientists also highlighted its scarcity on Earth but relative abundance on the Moon’s regolith and in gas giant atmospheres.
