John Coutre, age 10, of Libertyville, Illinois, for his question:

Exactly how do snowflakes form?

It seems logical to suppose that snowflakes form from frozen raindrops, or perhaps from misty cloud moisture. But this does not happen. True, they do form from moisture, but this moisture is in the form of gaseous molecules of water vapor. When the air temperature dips down around zero, the vapor freezes from a gas to minuscule crystals of solid ice. Weather conditions must be just right for snow making and it takes millions of these scattered midgets to form one flake.

Lab experiments suggest that they must be coaxed to cling together in feathery masses. The temperature helps, so do small, solid fragments of dust, salt and ice floating in the air. The shape of water molecules makes them form six sided ice crystals. Millions of the tiny, six sided crystals arrange themselves in a six sided snowflake. They build their lacy designs around millions of tiny pockets of air. The neat, frothy mixture of air and ice robs the crystals of their glassy glitter and the snowflake, naturally, is snow white.