A potential fuel for nuclear fusion, Helium-3, has long been thought to be scarce on Earth. However, recent atmospheric samples have revealed an unexplainably high concentration of the isotope. Helium-3 is a potential fuel for nuclear fusion reactors, with one tonne capable of providing electricity for seven million people for a year. Scientists from the University of California San Diego have published a study in Nature Geoscience, revealing an unexplainable Helium-3 concentration on Earth. The team discovered this while determining the Helium-4 content in the atmosphere. They analysed 46 atmospheric samples taken between 1974 and 2020, developing a new method based on the ratio of Helium-4 to nitrogen to determine the concentration. The study found that the concentration of Helium-4 in the atmosphere has significantly increased over the past 50 years, indicating that the concentration of Helium-3 has also increased. This is significant as Helium-3 is only found in minimal amounts on Earth.
The increase in Helium-4 concentration in the atmosphere is not due to anthropogenic emissions from natural gas, nuclear weapons, or nuclear energy generation. The source of the Helium-3 concentration remains unknown, as it is only produced in small amounts through geologic processes, nuclear weapon testing fallout, and solar winds. The scientists cannot explain the origin of the Helium-3 concentration, which exceeds previous estimates of anthropogenic emissions. The study’s findings suggest that previous isotope measurements may have been incorrect or that there are unknown sources of Helium-3 on Earth.
The discovery of an unexplainable Helium-3 concentration on Earth is significant as it challenges previous assumptions about the scarcity of the isotope. The potential for Helium-3 as a fuel for nuclear fusion reactors could revolutionize energy production, and this discovery may lead to further research into the isotope’s origin and potential uses.
