The water cycle follows a cycle of evaporation, condensation, precipitation and collection. Water on Earth is always moving. It is constantly being recycled. This is called the water cycle.

The study appears in the journal Science. "If we want to predict the effects of climate change on Earth's water resources, we need data showing how the hydrologic cycle will respond at a small ...

but there's no telling what it could offer to science after that. "Making high-resolution measurements of the type and amount of lunar water will help us understand the lunar water cycle ...