Interlune presents excavator for helium-3 mining on the moon

Helium-3 could be an important raw material for the future and could be used as a fuel for fusion power plants, for example. However, the isotope is very rare on Earth. Interlune therefore wants to mine it on the moon. The US company has presented the prototype of a mining system.

It is a full-size excavator designed to dig up regolith, i.e., moon dust, on the moon. It was built by Interlune in cooperation with the US mechanical engineering company Vermeer Corporation. Both companies tested a scaled-down model last year.

However, dredging is only one part of the process of extracting helium-3 from the lunar soil, Interlune explained. A total of four steps are required: dredging, sorting, extracting and separating. The excavator will be in continuous operation and process 100 tons in one hour.

Gary Lai, one of the founders and technical director of Interlune, said that such a working speed is necessary to extract helium-3 in large quantities on the moon. This has “never been attempted before, let alone with great efficiency.”

No information on size and weight

Interlune has not provided any information about the size and weight of the machine. However, the machine must be of a certain size to be able to perform such work. This raises the question of how it will get to the moon – and how much it will cost.

Helium-3 is a stable isotope of helium with two protons and one neutron. It is a good source of energy: one ton should be enough to supply a city with seven million inhabitants with electricity for a year. It is also used as a coolant in quantum computers.

The isotope hardly occurs on Earth. It is a component of the solar wind, which does not reach the Earth's surface – thanks to the Earth's magnetic field. However, the moon has no magnetic field to keep the solar wind out. This is why helium-3 has accumulated there.

Interlune wants to mine the isotope on the moon and then transport it to Earth. The company counters the argument of the high cost of such an undertaking with a high price. The price is currently stable at 20 million US dollars per kilogram, Interlune boss Rob Meyerson told the US online medium Spacenews at the beginning of the year. Interlune wants to mine several dozen kilograms of helium-3 per year and transport it to Earth.

However, it is unclear how much helium-3 is actually contained in the regolith. There is too little measurement data to estimate whether the concentration is high enough to make mining worthwhile.

(wpl)