Water is as important as rockets in lunar exploration. It is essential not only for the survival of astronauts but also as rocket fuel. A British startup has developed technology to produce clean water from lunar ice using microwave principles.
The international competition "Aqualunar Challenge" noted that Naicker Scientific developed technology to extract drinking water from frozen lunar soil using ultrasonic methods, winning first place on the 28th. The Aqualunar Challenge is a competition jointly promoted by the UK Space Agency and the Canadian government.
Scientists believe that a large amount of water is stored in the form of ice in the permanently shadowed areas at the lunar south pole. Water serves as drinking water for astronauts, and the byproducts, oxygen and hydrogen, can be used for respiration and as rocket fuel. However, the moon's extreme cold and near vacuum conditions, combined with gravity that is only one-sixth that of Earth, make it difficult to process ice and obtain water.
The Aqualunar Challenge solicited technologies that can produce drinking water from soil mixed with ice at the lunar south pole. Naicker gained attention for a method called "SonoChem." While most participating teams focused on purifying contaminated ice, they proposed a method that first evaporates water from the soil and then purifies it.
First, the lunar soil mixed with ice is heated in a microwave. The soil remains while water and contaminants evaporate into gas. Later, this gas is collected and turned into liquid. Afterward, ultrasonic waves are emitted to generate millions of tiny bubbles, and the high temperature and high pressure explosions that occur when the bubbles burst break down or evaporate the contaminants, ultimately leaving only clean water.
Naicker explained that in this experiment, they used construction sand instead of actual lunar soil and did not directly drink the purified water. The Naicker research team plans to concurrently research the production of rocket propellant fuel using the same technology. They also confirmed that ultrasonic technology is effective for removing various contaminants such as pharmaceuticals and pesticides.
In this competition, the second and third place teams also received attention for their innovative technologies. The second place was taken by RedSpace. They separated volatile gases by heating soil in a sealed space. Then, they filtered the remaining mixture of water, methanol, and soil to remove solids and used distillation to separate water and methanol.
The third place team from Queen Mary University of London melted lunar ice and subjected it to a temperature exceeding 373 degrees Celsius and a pressure of 220 atmospheres, creating a supercritical state that does not belong to liquid, solid, or gas. They then proposed a technology that causes a strong oxidation reaction to remove contaminants all at once.
References
Aqualunar Challenge (2025), https://aqualunarchallenge.org.uk/news/announcing-the-winners-of-the-aqualunar-challenge/