Moon water limits lunar city size, scientists say

Scientists say the moon lacks sufficient water to sustain large cities, dashing hopes of a lunar metropolis. A study published Monday in Frontiers in Space Technologies estimates that even a generous 1 billion tons of water trapped in glass beads would support a million-person city for under two and a half years without recycling. With efficient recycling at 98%, matching the International Space Station's rate, that same city could last 100 years, though researchers doubt such disciplined water use is sustainable. A smaller city of 100,000 people could survive 1,000 years, while a town of 10,000 might last 10,000 years, potentially allowing time for future water imports from asteroids or Saturn's moons. Experts suggest a lunar town could emerge within 30 years, not the 10-year city timeline proposed by Elon Musk. They stress the need for international regulations to prevent a "gold rush" that could deplete the scientifically valuable water ice at the lunar poles.