Snow - Did You Know?

Are all snowflakes unique? Yes and No, depending on your definition. Nano-snowflakes can be exactly alike, but this means looking at snowflakes on a very small scale (1-100 nanometers). Small snow crystals can look similar to one another with their hexagonal shape under a microscope. Large complex snowflakes have over a hundred features that can form in different ways, meaning there are more 10¹⁵⁸ (that’s 1 with 158 zeros behind it!) different snowflakes. So it’s unlikely that any two complex snowflakes have ever looked completely alike in the history of the planet.

Source: Snow Crystals | CalTech ITS