Scientists say Moon ice stored 1.5 billion years in the lunar polar regions could reshape how future space missions are planned. A new study says the Moon has been steadily building up and preserving water ice in permanently shadowed regions, known as cold traps, over an immense span of time.
The research, based on data from NASA’s Lunar Reconnaissance Orbiter, suggests this was not a one-time event. Instead, water from sources such as comets and solar wind appears to have accumulated gradually as the Moon’s polar conditions changed.
The strongest finding is a link between the age of a cold trap and the amount of water ice it contains. Younger permanently shadowed regions, formed around 100 million years ago, tend to show more exposed surface ice.
Older cold traps, however, appear to contain buried ice protected beneath regolith, or lunar soil. That pattern suggests the Moon’s poles have gone through a long-term cycle of ice accumulation, burial and preservation. The study also says the Moon’s axial tilt decreased over time. As a result, more regions fell into permanent darkness, allowing additional water ice to remain stable in temperatures cold enough to preserve it for billions of years.
The Moon’s changing axial angle helped create and expand these cold traps. Because permanently shadowed regions remain below extremely low temperatures, water molecules and ice can survive there for very long periods.
The Moon’s polar environment acted as a natural storage system. Over time, expanding dark and frigid regions captured and preserved more ice. That process helps explain why some craters may contain more buried ice than others. It also shows that lunar ice does not spread evenly across the surface, a finding that could shape future mission planning and extraction strategies.
The study also points to the practical value of this ancient ice. Future missions could use it as an in-situ resource for drinking water, oxygen, and even hydrogen-based rocket fuel. That potential makes the Moon more than a scientific target. It could also serve as a staging point for deeper space exploration, including eventual missions to Mars.
Still, the ice may mix with soil and lie buried at different depths depending on where and when it formed. As a result, future extraction efforts will likely require careful planning and precise targeting. Overall, the findings strengthen the case for exploring the Moon’s polar regions not only for science, but also for long-term human spaceflight.
