Snow way! There AREN'T an infinite number of snowflake shapes - there are just 35 and they're ruled by temperature and humidity

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Snowflakes are understood to be unique - at a molecular level at least.

But scientists have revealed that each and every one of them can in fact be sorted into 35 general shapes, which in turn tell experts how they formed.

The shapes, which include column crystals, irregular snow particles and plane crystals - which make ‘traditional’ hexagonal snowflakes - vary according to temperature and humidity.

Snowflakes can occur in a huge variety of shapes. This infographic shows the basic levels of classification for the 35 shapes, which are then subdivided into 121 categories, decided by researchers at the Kitami Institute of Technology in Hokkaido, Japan

Bournemouth-based chemistry teacher Andy Brunning, created an infographic based on recent research to show the different shapes, which he published on his blog, Compound Interest.

It shows 39 types of ‘solid precipitation’ or snow, including the 35 types of snowflakes and their names, which can be further divided into 121 subtypes.

Simpler snowflake shapes such as germ of ice crystals, are more common at low humidities, while more complex flakes, such as plane crystals are formed in areas of high humidity.

Simpler snowflake shapes such as germ of ice crystals, are more common at low humidities, while more complex flakes, such as plane crystals (a stock image is pictured) are formed in areas of high humidity

‘We still don’t know the precise variables behind the formation of particular shapes, although researchers are continually working on theoretical equations to predict snowflake shapes,’ Mr Brunning wrote. 

The latest study by researchers at the Kitami Institute of Technology in Hokkaido, Japan, splits the classification into three levels: general, intermediate and elementary, with the graphic showing the 39 intermediate categories. 

These are sorted into eight groups: Column crystals, plane crystals – which are what many people imagine snowflakes look like – a combination of column and plane crystals, aggregation of snow crystals, rimed snow crystals, germ of ice crystals and irregular particles, one of which looks a little bit like a fern.

The number of elementary categories used to explain snow crystals has increased from 21 in the early 1930s, to 42 in the 1950s, 80 in the 1960s and now stands at 121, as of 2013. 

Snowflakes are of interest to scientists who not only want to understand their formation, but also wish to find out how crystals could be used in different applications, such as in silicon and semiconductors.

The study of snowflakes falls within crystallography – the exploration of crystal structures – which allows chemists to determine the arrangement of atoms in solids.

‘Crystallography works by passing X-rays through the sample, which are then diffracted as they pass through by the atoms contained therein,’ Mr Brunning explained.

‘Analysis of the diffraction pattern allows the structure of the solid to be discerned.’

The technique was used by Rosalind Franklin to photograph the double helix arrangement of DNA prior to Watson and Crick’s confirmation of its structure.

BIRTH OF A SNOWFLAKE: BEAUTIFUL VIDEO REVEALS THE FORMATION OF DELICATE ICE CRYSTAL

Last year, a man has created a beautiful video showing how snowflakes flakes grow to form their shapes under a microscope.

Russian video maker Vyacheslav Ivanov filmed the formation of hexagonal ice crystals to produce a two minute ‘microscopic time-lapse'.

The flakes are created when a water droplet freezes around pollen or a speck of dust in the air, creating an ice crystal.

Russian video maker Vyacheslav Ivanov filmed the formation of hexagonal ice crystals to produce a two minute ‘microscopic time-lapse'. This is a still from the video, which shows a water droplet freezing around a speck of dust to create an ice crystal

Then more water molecules land on the crystal, creating the hexagonal shape as they extend six ways along the ‘arms’.

These ice crystals that make up snowflakes are symmetrical because they reflect the internal order of the crystal’s water molecules as they arrange themselves in predetermined spaces to form a six-sided snowflake, the National Oceanic and Atmospheric Administration (NOAA) explained.

The reason that some flakes have six lines of symmetry is because of the hydrogen bonds in water crystals.

As the water freezes, bound-together water molecules crystallise into a hexagonal structure so that each point on a hexagon is an oxygen atom with hydrogen bonded to an oxygen atom on each side, iO9 reported.

As the freezing process continues, more water molecules are added to the microscopic structure, causing it to bloom outwards along its six sides and transforms into what we recognise as a snowflake.

The precise nature of the shape created depends upon the temperature and the humidity.

Long, needle-like crystals form at slightly warmer temperatures like-5 degrees Celsius, whereas flakes that form in cooler temperatures such as -15 degrees Celsius are flatter and more circular in shape.