Explained: The making of snowflakes
Some celebrations and seasons are associated with a few unique natural phenomena. Christmas, for example, is related to snowflakes. Seeing these beautiful crystal pellets on their sweater sleeves amuses kids during the festive season. These are nothing but water molecules in a crystallized form. They fall from the clouds to the surface of the earth in the form of beautiful hexagonal prism structures. These water molecules may look like dust from afar but have unique shapes when examined under a microscope. Extensive research has revealed that water molecules take the shape of tiny crystals in humid temperatures. It is also observed by scientists that the most intricate snowflakes form when moisture is present in the air that can combine with the falling water molecule.
How are snowflakes formed?
A snowflake typically begins to form when an extremely cold-water droplet freezes in the air forming dust-like particles. The ice crystals that make up the exterior of the snowflakes are symmetrical, having distinct patterns reflecting the interior arrangement of molecules. The molecules then take the shape of a predetermined six-sided pointy crystal. It is the temperature condition that forms the snowflake and determines its shape as it hits the ground. The arm of the snowflake grows according to the surrounding temperature and humidity level in the air. The six-sided shape is mostly maintained but, the crystal may branch off in multiple directions to new shapes.
The ice crystal is heavier than the surrounding air as it falls from the sky and it is due to the humid air that more water vapor freezes into crystallized shapes. This freezing process is very systematic. The water molecules are arranged in a way to repeat the structure of the crystal. The snowflakes grow larger and larger as they fall, only varying in geometry. As they pass through a layer of thin, warm air, partial melting can take place. After the warm air has passed, the snowflakes take the shape of crystal pellets once again making millions of tiny snowflakes in the same way.
Types of snowflakes
Snowflakes come in a variety of shapes and sizes. The intricate patterns and structures appear so unique, especially under a microscope. The most common snowflake shape is that of a hexagon, the six-fold radial symmetry. Every snowflake has a different shape because each pellet tumbles through the air, spiraling down and taking different paths to the ground. These crystal pellets float through the clouds with different temperatures and moisture levels producing arms of different lengths and types. Here's a lowdown on the different shapes and sizes of the most common snowflakes:
Stellar dendrites: These are the most recognizable, star-shaped snowflakes with side branches. They are common tree-like structures.
Needles: An alternative name suggests ‘column snow’ for these needle-shaped snowflakes. They are small and easy to miss when seen by the human eye. Other characteristics include the long and slender-shaped snowflakes that are hollow at both ends.
Fernlike stellar dendrites: These are larger, leafier snowflakes with branches that resemble a fern. The largest snow crystals are not always symmetrical.
Diamond dust particles: These are tiny snow crystals that look like sparkling dust in the sunlight and are the smallest crystals with a diameter that is no larger than human hair. These dust-like particles are often found in bitterly cold weather.
Twelve branched snowflakes: When two six-branched snowflakes collide and mix in the air they grow into a twelve branched crystal.