Ice has usually started to fall from the sky by mid-November in central Maine, so brace yourself.

Snowflakes are intricate crystals of ice that form from when water vapor in the clouds condenses directly into ice. All snowflakes are based on the same six-armed pattern, but the chances of finding two identical snowflakes is extremely small. Though the basic formula is the same, the possible shapes are almost infinite.

In order for snow crystals to form, the top of the cloud must be at least 32 degrees Fahrenheit. However, the crystals do not actually start to form until about 14 degrees. The complexity of a snow crystal also depends on the humidity of a cloud. The lower the humidity, the simpler the shape is, and the higher the humidity is, the more complex they are.

Snowflakes are not actually white. They are clear. The reason people think they are white is because when you see a snowbank, the light passes through the crystals. All the colors are evenly distributed throughout the crystals, combining to give the mirage of a white color.

Snowflakes also help heat space itself! In the North and South Poles, the ice is very reflective, and when the sun’s heat hits it, it is reflected back into space.

One cubic foot of snow can contain 10 million flakes. If all the snow that has ever fallen were accumulated at one time, it would be 50 miles deep over the entire Earth.

Welcome to winter.