A Seattle-based startup, Interlune, is advancing plans to mine the moon for helium-3, an isotope of helium with significant industrial and potentially energy applications. The company aims to begin experimental lunar extractions as early as 2028, targeting an estimated 20 quadrillion dollars worth of the resource.
Helium-3 is highly sought after for its potential use in advanced technologies, including cooling magnets for quantum computers and as a fuel for low-radioactivity nuclear fusion reactors. While helium is common on Earth, helium-3 is scarce, primarily obtained from the decay of tritium in nuclear weapons. Its abundance on the moon is attributed to billions of years of solar wind bombardment due to the moon's lack of atmosphere and a strong magnetic field.
"The sun spews it out in all directions," explained Gary Lai, Interlune's chief technology officer. "The moon doesn’t have an atmosphere or a strong magnetic field, so for billions of years it’s just been collecting on the surface."
Interlune's strategy involves crushing lunar soil, known as regolith, and then using deep cryogenic distillation to separate the helium-3. This process leverages the fact that helium-3 remains a gas at temperatures just above absolute zero, while other components of the lunar soil's gaseous emissions would liquefy. The company has reported success in extracting 99% pure helium-3 from terrestrial helium using its cryogenic technology, a process deemed crucial for lunar extraction.
Despite past skepticism labeling lunar helium-3 extraction as "moonshine," Interlune has secured significant funding, including a $6.9 million contract with NASA. The company is also seeking partnerships within Australia's mining sector, seeing synergy with the Australian Space Agency's work on regolith-transporting rovers.
The pursuit of lunar helium-3 is not exclusive to the U.S. China is also investing in technology for its extraction and return to Earth. However, Interlune's leadership expressed confidence that competition would not lead to conflict, citing the vastness of the moon and existing international cooperation on peaceful space exploration.
"The moon’s a very, very big place, and we don’t see a conflict developing in terms of where China wants to go, where we want to go and where other nations are focused," said Indra Hornsby, Interlune's chief operating officer.
Interlune plans to begin with small-scale operations, extracting an estimated 10 to 20 kilograms of helium-3 in its initial five years, a fraction of the estimated billion kilograms present on the moon. The company's ambitious timeline is contingent on the success of NASA's Artemis III mission, which aims to return astronauts to the lunar surface by 2028.