Why Are Snowflakes Symmetrical?

Snow in Suffolk

Mystery Hour Question

Why are snowflakes symmetrical?

Jed, Wigan.


Name: Professor Hal, Brighton

Qualification: Professor of Public Understanding of Science, University of Brighton.

Answer: *definitive* This is all to do with thermodynamics and crystals forming; a snowflake starts off as a little bit of dust or ice, upon which molecules of water will fit in to where they do best. Tessellations – identical patterns which expand to make larger patterns - are a great example for this.

Thermodynamics states that a system must find the lowest order of pressure in order to form itself, so each separate molecule of ice will try and fit in to the space.