Current estimates indicate that the upper ten meters of the lunar surface contain enough elemental oxygen to form enough O2 For every person on earth for the next hundred thousand years - more than enough for settlement on the moon!
When it comes to the future of space exploration, there are some practices that are essential for mission planners. The most important of them is the concept of using resources in place (ISRU), providing food, water, building materials and other essentials using local resources. And when it comes to missions that will refine the moon and Mars in the coming years, the ability to collect ice, regolith and other elements is critical to the success of the mission.
In preparation for the Artemis mission, NASA planners are focusing on finding the best way to produce oxygen gas (O2) from all the elemental oxygen trapped in the dust of the lunar surface (called the lunar regolith). In fact, current estimates indicate that the upper ten meters of the lunar surface contain enough elemental oxygen to form enough O2 For every person on earth for the next hundred thousand years - more than enough for settlement on the moon!
The moon does have a very thin atmosphere containing elemental oxygen, but it is so weak that scientists characterize the moon as a "body without air". But within the lunar regolith, the fine dust and rocks that cover the lunar surface, there are abundant amounts of oxygen in the lunar regolith rocks. This fine dust, also called "moon dust", penetrates in front of the moon and is the result of billions of years of collisions of meteors and comets.
According to John Grant, a lecturer in earth sciences at Southern Cross University, Australia, the oxygen content of the moon's crust is about 45%. But the oxygen is associated with oxidized minerals - especially silica, aluminum, iron and magnesium. The isotopic composition of these minerals is almost identical to the minerals on Earth, and this has led to theories that the Earth and Moon system formed together billions of years ago (the giant collision hypothesis).
But in order for the astronauts and future moon dwellers to be able to use this oxygen, it has to be taken out of all this regolith, and it requires a large amount of energy to break the chemical bonds. On Earth, the use of this process (called electrolysis) is common in the production of metals, when an electric current is applied to molten oxides to separate the minerals from the oxygen.
In this case, the oxygen gas is produced as a byproduct so that metals can be extracted for construction and manufacturing. But on the moon, the oxygen will be the main product, while the metals will be put aside as a by-product that might be useful - most likely for building residences. As Grant explained in a recent article in The Conservation, the process is simple but there are two major problems with fitting it into the space:
"He devours energy. To be applicable, it would need to be powered by solar power or some other energy source available on the moon. Extracting oxygen from Margolit will also require a lot of industrial equipment. We will first need to transform a solid metal oxide into a liquid form, by using heat, or heat together with solvents or electrolytes. We have the technology to do this on Earth, but transporting this equipment to the moon - and generating enough energy to operate it - will be a huge challenge."