Nanjing University scientists believe they can use compound present in lunar soil to produce oxygen and fuel locally to support crewed moon missions.
The "extraterrestrial photosynthesis" strategy requires electrolyzing moonwater into oxygen and hydrogen using lunar soil. According to the new research, carbon dioxide exhaled by astronauts can be combined with hydrogen produced by water electrolysis to produce hydrocarbons such as methane, which could be used as fuel.
According to an analysis of samples returned to Earth by the Chang'e 5 rover, lunar soil could be used to produce oxygen and other products via chemical reactions that mimic photosynthesis. Reliable supplies of such materials are required for any future lunar base.
It is costly to launch supplies into space, so any material that can be found on the moon and does not need to be brought from Earth can save a significant amount of money.
Yingfang Yao of Nanjing University in China and his colleagues investigated a lunar soil sample to see if it could be used as a catalyst in a system that would convert carbon dioxide and water produced by astronauts' bodies into oxygen, hydrogen, and other useful byproducts such as methane that could be used to power a lunar base.
To identify catalytically active components of the soil, Yao and his colleagues used techniques like electron microscopy and X-ray diffraction on their sample. They discovered high levels of iron and magnesium-based compounds, which could be useful in a reaction similar to green plant photosynthesis.
The new research could be useful for China, which is preparing a joint moon base with Russia. The International Lunar Research Station (ILRS) will be robotic at first, but astronauts are expected to be able to visit by the mid-2030s. China's Chang'e 8 mission is scheduled to launch later this decade to test technology for using local resources and 3D printing in manufacturing.
The team is now working on a system that will use lunar soil and solar radiation. The article, which was released publicly today in the journal Joule, is part of a study looking into how to use resources on the moon to aid human exploration. It would be less expensive to transport vital resources from Earth if they could be produced locally.
NASA's Artemis program also aims to establish a long-term, sustainable human presence on the moon. Artemis intends to return people to the lunar surface in 2025, followed by the establishment of a research outpost near the lunar south pole a few years later.
Chang'e 5 launched in November 2020 and returned to Earth a month later with 3.81 lbs (1.731 kilograms) of lunar material. It was the first successful lunar sample return since the Soviet Union's Luna 24 mission in 1976.