Astronauts require three essential resources to survive on the Moon: water, oxygen and fuel. These form a crucial part of long-standing plans to establish a permanent lunar base.
Recent technological advances could make life on the Moon possible by extracting water from lunar soil and producing necessary ingredients for fuel.
A study published recently in Joule reveals that the technology can successfully extract water from soil samples and convert carbon dioxide into oxygen and fuel chemicals. This breakthrough could increase the feasibility of life on the Moon while reducing the need to transport resources from Earth.
Hunting for water on moon
Human habitation on the Moon depends on the availability of water, often described by scientists as ‘liquid gold’ due to its rarity and value. Fortunately, several sources of lunar water have emerged in recent years. Most exist as ice trapped in permanently shadowed craters near the Moon’s poles. Other evidence appears in mineral grains and glass beads formed by asteroid impacts.
In late 2020, the China National Space Administration’s Chang’e 5 lunar mission returned soil samples to Earth. Since then, scientists have identified traces of hydroxyl (OH) and molecular water (H2O) but have yet to determine the precise locations of water on the lunar surface.
Two main theories prevail about the origin of lunar water. One suggests that comets and asteroids delivered water during impacts. The other proposes that solar wind implants hydrogen ions into lunar soil, which combine with oxygen to form hydroxyl or water molecules.
Supporting astronauts on moon
Supplying a lunar base with water from Earth would prove prohibitively expensive. According to the new study, the cost of transporting one gallon of water by rocket amounts to roughly $83,000. Each astronaut consumes approximately four gallons of water daily.
However, researchers have developed new technology to address this problem. Previous extraction methods demanded excessive energy, involved multiple steps and failed to convert carbon dioxide into fuel reliably.
To improve efficiency, scientists designed a photothermal process that converts light into heat. This method underwent testing on Chang’e 5 lunar soil samples as well as simulated samples. The process uses a batch reactor filled with carbon dioxide gas, operated by a light-concentrating system.
The technology simultaneously extracts water and converts carbon dioxide into carbon monoxide and hydrogen gases. These gases serve as fuel and oxygen sources to sustain astronauts.
‘We never expected the lunar soil to contain such “magic”,’ said Lu Wang of the Chinese University of Hong Kong, Shenzhen. ‘The greatest surprise was the success of this integrated approach. Extracting lunar water and catalysing photothermal CO2 in a single step increases energy efficiency while reducing costs and infrastructure complexity.’
Remaining challenges
Despite success on Earth, researchers caution that deploying photothermal technology on the Moon faces challenges. Extreme temperature fluctuations, radiation exposure and low gravity could impede water extraction.
To realise a lunar habitat, experts insist on overcoming technical hurdles and controlling development costs for water extraction in the future.
