Did You Know? #47

What are the odds of finding two identical snowflakes?

There is no fundamental law of the universe that says snowflakes cannot be identical, but since each flake is made of millions of randomly arrayed water molecules that aren't quite uniform, the odds of finding twin flasks are astronomically slim, about 1 in 10 to the 158th power. Snowflakes develop when water molecules freeze together, and not every water molecule is identical. The vast majority feature oxygen atoms with 8 neutrons while some contain 10 neutrons--the molecules have subtly different shapes, which leads to slightly different forms when they freeze.