Noctilucent clouds on Earth are something quite spectacular, thin structures so high that they can still catch sunlight long ...

This process is called evaporation. The water vapour rises and collects in the sky as clouds. When the water vapour cools down, it condenses, turning back into liquid, and falls back to earth as ...

It follows a cycle of evaporation, condensation, precipitation and collection. The sun heats up water on land, in rivers, lakes and seas and turns it into water vapour. The water vapour rises into ...