Lunar ice reserves too small for permanent city, study finds

A new study from the Harvard–Smithsonian Center for Astrophysics finds that the Moon's existing ice reserves are insufficient to support a permanent lunar city, casting doubt on recent colonization plans. The research, published in Frontiers in Space Technology, calculated that a city of one million people using 500 tonnes of water per person would run dry in a few years without recycling. Even with International Space Station-level efficiency, such a city could only last about 100 years. Energy would not be a problem, as solar power is abundant, but water scarcity remains critical. The study suggests a sustainable population would be capped at around 1,000 people, though deeper ice reserves could potentially be discovered in the future.