Do you remember the thrill of the first snowflake that you caught on your tongue as a child? Do you remember the way cold air rushed into your mouth, the way you over strained your tongue to make sure you caught it and the way it tingled on your tongue once it landed? It was spectacular! Like so many joys of childhood and life, really, it is a very simple thing. Or, is it?

It is always snowing somewhere in the world and as a result, we take snow for granted. If we consider what it actually takes for snow to form at a molecular level, it