In addition to advances in space exploration, we see that a lot of time and money has been invested recently in producing technologies that can enable efficient use of resources in space. At the forefront of these efforts is finding the best way to produce oxygen on the Moon.
In October, the Australian Space Agency and NASA agreed to send a survey probe to detect Moon rocks that could enable oxygen production on the Moon as part of the Artemis program. The Moon has an atmosphere, but is very thin and mostly made up of hydrogen, neon, and argon. It’s not the kind of gas mixture that could feed oxygen-dependent mammals like humans.
However, there is actually plenty of oxygen on the Moon. The only problem is that it doesn’t stay in gaseous state. Instead, it waits trapped in regolith, the layer of rock and fine dust that covers the Moon’s surface. If we could extract oxygen from the regolith, would it be enough to support human life on the Moon?
The lunar ground mostly contains minerals such as silica, aluminum, iron and magnesium oxide. All these minerals have oxygen in them, but our lungs cannot access this oxygen. “Moon soil” is actually a misnomer, and scientists don’t use the term. Because when we say soil, we are talking about a material that has been shaped by the influence of organisms over millions of years. Soil, as we understand it on Earth, has very special physical, chemical and biological properties. The material on the surface of the Moon is in its original, untouched form and is called regolith.
The Moon’s regolith consists of approximately 45% oxygen. But the oxygen remains firmly bound to the minerals in the regolith. Energy is required to break this bond and create oxygen.
The electrolysis method, which is widely used in the world, is used to separate aluminum from oxygen. If a similar method can be applied on the Moon, it may be possible to produce oxygen from the regolith and aluminum which can also be usefully used as a byproduct. However, this requires a large amount of energy. On the Moon, this energy can be obtained from the Sun or other energy sources found on the Moon.
If we can achieve this, how much oxygen can we produce on the Moon? Recent studies show that this amount is quite high. Calculations using only the surface accessible regolith show very promising results. Each cubic meter of lunar regolith contains 1.4 tons of minerals, from which it is possible to obtain 630 kilograms of oxygen. A person consumes about 800 grams of oxygen per day. 630 kilograms of oxygen can keep a human alive on the Moon for two years. The ten-metre layer of the regolith contains enough oxygen to keep eight billion people on Earth alive for 100,000 years.