Helium-3 from the Moon

The idea of ​​extracting helium-3 from the Moon has been discussed for a long time and is finally about to become a reality thanks to the initiative of the Seattle-based company Interlune. The company announced its plans to begin commercializing lunar helium-3, intended for use in various future applications here on Earth.

Interlune was founded by Rob Meyerson and Gary Lai, former executives of the space company Blue Origin, and can count on the experience of its executive president, former astronaut Harrison Schmitt, who walked on the lunar surface together with Eugene Cernan during the mission Apollo XVII, NASA's last venture on the Moon. The company has operated almost in secrecy since its founding in 2022, and only recently came out into the open to announce that it had raised over $30 million in funding, an important first step that promises to have major developments.

The discussion on the lunar economy has attracted interest, but often without fully clarifying its concrete meaning. Many Moon-related corporate ventures appear to focus on selling services and products to NASA or other government agencies, raising questions about real market demand. In this context, helium-3 emerges as one of the first examples of a lunar resource with potential economic value on Earth. However, numerous questions remain regarding the proposal, both from a technological and economic point of view. The first concerns the feasibility of plans for the creation of a robotic excavator capable of extracting helium-3 from the "regolith", the abrasive material that covers the lunar surface, and to develop an automatic process for collecting and transporting the precious gas on earth. Equally crucial is assessing whether the conditions exist for a sufficiently large and stable market for this hydrogen isotope here on Earth.

Despite the unknowns, Interlune is convinced that it is the right time to start a mining company on our satellite, especially considering NASA's huge investments in the Artemis program, which will bring humans back to the Moon. Looking to new spacecraft, innovative energy sources and infrastructure under development, company executives are optimistic about the sustainability of producing helium-3 on the Moon, despite the high costs of extracting and transporting it to Earth.

The importance of helium-3

Made up of two protons and a neutron, helium-3 is a stable isotope lighter than the common helium that fills party balloons. On Earth it is present in very limited quantities, as a by-product of radioactive decay, nuclear weapons tests and fission reactors. In the Universe it is relatively more abundant and is produced in the fusion processes that take place in the core of stars. In the case of the Sun, helium-3 is transported by the solar wind to the vicinity of the Earth, but the Earth's magnetosphere diverts this flow of particles away from the planet. Since there is no magnetic field around the Moon, considerable amounts of helium-3 are believed to have accumulated on the lunar surface over billions of years.

There is a growing demand for this isotope, currently used as a coolant for quantum computers and superconductors, especially considering its potential as a fuel for future thermonuclear power plants. Companies like Helion Energy and Princeton Fusion Systems have already planned to use helium-3 along with deuterium to power their fusion reactors. The main advantage derives from the nature of the reaction of helium-3 with deuterium: it is an "aneutronic" fusion, i.e. without neutron emission, which can generate considerable quantities of energy without making the surrounding material radioactive. However, it is important to note that the temperatures required to initiate helium-3 fusion reactions are significantly higher than those needed for traditional fusion reactions. [Future article?]

Given its extreme rarity and the increase in use in the technological sector, the price of helium-3 has undergone drastic changes in recent years, reaching $3,000 per litre. Forecasts indicate further growth in demand which could lead to a significant increase in prices. According to Interlune, this prospect would justify the enormous investments needed to extract helium-3 from the lunar surface.

Mining on the Moon

The Interlune challenge is based above all on an innovative system to separate helium-3 from lunar dust. Although it is very likely that there are significant quantities of this isotope on the surface of the Moon, the extraction process will be far from simple. Hundreds of tons of "regolith" will need to be processed to obtain just a few kilograms of helium-3 to bring back to Earth. For this reason, the company has developed an energy-efficient extraction process. The key technologies involve excavation, extraction and separation of the isotope from lunar soil. The methods developed require only a tenth of the energy used by similar technologies, which allowed Interlune to win the 250 thousand dollars funding offered by the National Science Foundation to encourage the development of mining processes on the Moon.

The company is planning a demonstration mission that will analyze the lunar “regolith” and try to extract a small amount of helium-3. This exploratory experiment will be conducted in 2026 as part of one of NASA's first commercial missions. The next phase plans to build a pilot plant in 2028, with the aim of starting extraction operations by 2030. If all goes according to plan, the first quantities of lunar helium-3 could be available on terrestrial markets as early as next decade.

To transport the precious element to our planet, Interlune is considering companies such as SpaceX or Blue Origin, both involved in developing vehicles capable of landing on the Moon and transporting cargo between lunar orbit and Earth. In fact, the company aims to exploit the commercial services offered by other companies, including the lunar rovers that NASA is financing for the Artemis missions but which will also be used by private companies.

In short, the extraction of mineral resources from other celestial bodies is becoming technically and economically feasible. In the future, we may see a new gold rush, but this time the "new frontier" could be the Moon.