Freshly Baked Science
Snowflakes are One of a Kind?
3rd December 2018
There is no better feeling than opening your curtains in the morning to see a fresh blanket of snow. When you look at it from afar, it’s hard to imagine that all of it is made up of loads of tiny snowflakes!
I’m sure you have all heard that there aren’t two snowflakes alike. Well, this isn’t entirely true! Snowflakes come in many different shapes and sizes, with most of them being slightly different from the others, but it wouldn’t be impossible to find two identical snowflakes.
Snowflakes are made up of ice crystals, dust and water vapour. It will start to form when a tiny particle of dust or pollen, in the atmosphere, comes into contact and becomes coated with water vapour. This freezes into a tiny crystal of ice, which forms the start of the snowflake. The molecules of water in the ice crystal arrange themselves into a hexagonal structure, which is why snowflakes are all 6 sided.
The ice crystal is heavier than the air surrounding it, causing it to start falling. As it falls, more water vapour freezes onto the surface. This freezing process isn’t just random, the water molecules arrange themselves to repeat the hexagonal structure. The snowflake keeps growing in this way as it continues to fall towards Earth.
The atmospheric conditions while the forming flake is falling determines the final shape of the snowflake. More moisture in the air, i.e. the higher the humidity, the bigger and more intricate the crystal. Really cold temperatures will create a plate-shaped crystal and a higher temperature will form a more branching pattern. The combination of the humidity and the temperature will result in a different flake shape and size.
Take a look at this time-lapse video of snowflakes forming! It’s mesmerising!
So to conclude, snowflake formation is dependent on the particle that the ice crystal forms around, the temperature and humidity. This is why snowflakes are highly unique, but if the exact same conditions are recreated, it isn’t impossible for another snowflake to form that is exactly the same as another!
We’d love to see your pictures of snow and snowflakes! Send them to us at firstname.lastname@example.org or via social media (@wonkscience) for a chance to feature on our website!