The third #winterwonderings post from our Science Correspondent, Samantha, we take a look at why frost makes patterns. Many countries have a mythical figure like Jack Frost, who draws in the ice and frost in winter, but what really causes these gorgeous natural designs.
First of all, ice and frost aren’t the same thing. Water freezes to become ice but frost is formed by crystals. These crystals are made when moisture in the air comes into contact with a solid surface that is colder than the freezing point of water. Instead of passing from its gaseous state (vapour) to liquid (water) and then to a solid (ice), the moisture goes straight from gas to solid. This causes frost crystals to form, as you can see in this video:
When frost crystals form on a smooth cold surface like glass, they often make beautiful patterns. Some people think that these look like leaves, some that they resemble ferns and others that they have the appearance of feathers. These patterns are the result of changes in the surface of the glass; tiny scratches, specks of dust or a faint smear of liquid soap can all affect the way that the crystals form and interlink.
Why don’t you see if you can spot some differences in the patterns next time it’s frosty?
Sam blogs about all kinds of science at www.samanthagouldson.com.