The European Space Agency (ESA) is working on an oxygen plant that can make breathable air out of simulated moondust. The aim is to one day use it on the Moon with actual moondust to, well, produce breathable oxygen.

“Being able to acquire oxygen from resources found on the Moon would obviously be hugely useful for future lunar settlers, both for breathing and in the local production of rocket fuel,” said Beth Lomax of the University of Glasgow in an ESA press release.

40–45% percent oxygen

Real lunar regolith is made up of 40–45% percent oxygen by weight. Lomax and her team are working on a system that can remove this oxygen from the simulated moondust and make it useable.

But the technique to do so is not so easy because the oxygen in the moondust is bound up chemically as oxides in the form of minerals or glass. This requires quite some complicated chemistry to extract.

According to the ESA, the extraction is “taking place using a method called molten salt electrolysis.” The method was invented by a UK company, Metalysis, for commercial metal and alloy production.

There is just one problem with this, and that is that Metalysis considered the oxygen an unwanted by-product, “which means the reactors are not designed to withstand oxygen gas itself,” explained Lomax.

So, Lomax and her team redesigned the system to be able to have the oxygen available to measure. Future upgrades will also see the oxygen stored.

A pilot plant

Now, the researchers are hoping to design a ‘pilot plant’ that could operate sustainably on the Moon.

“And now we have the facility in operation we can look into fine-tuning it, for instance by reducing the operating temperature, eventually designing a version of this system that could one day fly to the Moon to be operated there,” said ESA research fellow Alexandre Meurisse.

They are ambitiously targeting the first technology demonstrations for the mid-2020s. “ESA and NASA are heading back to the Moon with crewed missions, this time with a view towards staying,” said Tommaso Ghidini, Head of ESA’s Structures, Mechanisms and Materials Division.

“Accordingly, we’re shifting our engineering approach to systematic use of lunar resources in situ. We are working with our colleagues in the Human and Robotics Exploration Directorate, European industry and academia to provide top class scientific approaches and key enabling technologies like this one, towards a sustained human presence on the Moon and maybe one day Mars.”