Helium-3 is a light, non-radioactive isotope of helium produced in the Sun's fusion reactions and carried across the Solar System by the solar wind. Unlike Earth, which is shielded by its magnetic field and atmosphere, the Moon has been bombarded by this wind for billions of years. The particles become embedded in the lunar regolith, or soil, with meteorite impacts mixing them below the surface, creating a potential reservoir of the isotope.
The company, whose name has not been disclosed in the reports, believes it can rapidly extract helium-3 in quantities that would take millennia to accumulate naturally. The four-hour extraction time cited refers to the collection of an amount of helium-3 equivalent to what has been deposited by solar wind over 15,000 years. This would require processing vast amounts of lunar soil, likely involving heating the regolith to release trapped gases.
Helium-3 is considered a holy grail for fusion energy because it can produce power without generating neutron radiation, reducing the need for shielding and prolonging reactor life. However, no commercial fusion reactor currently operates on Earth, and known reserves of helium-3 are extremely limited. The Moon is estimated to contain about 1 million tonnes of the isotope in its upper few meters of soil, enough to power the Earth's energy needs for centuries if fusion becomes viable.
The Seattle venture is the latest in a growing field of companies and space agencies pursuing lunar resource extraction, part of a broader push to establish a sustainable presence on the Moon. NASA's Artemis program and China's International Lunar Research Station both envisage in-situ resource utilization, including helium-3 mining, as key to long-term lunar habitation.