Their prototype system mixes simulated lunar regolith — they have yet to try it with the real thing — with molten calcium chloride salt. The scientists then heat the mixture up to 950 degrees Celsius and run a current through it, releasing oxygen — a process called molten salt electrolysis. The electrolysis process has another useful byproduct: metal alloys. The scientists are also investigating applications to make best use of these alloys on the Moon. The team is looking to design a “pilot plant” that could be operated on the Moon by the mid-2020s.