The Science of Snowflakes, as an art form - some of the basics behind these miniature miracles of nature

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Caltech physics professor Kenneth G. Libbrecht has turned his passion for the study of ice crystals into an art form. In his books and website, snowcrystals.com, he breaks down some of the basics behind these miniature miracles of nature

Stellar Plates
These common snowflakes (above) are thin, plate-like crystals with six broad arms that form a star-like shape. Shapes like these form around 28 degrees Fahrenheit, while columns and slender needles appear near 23 degrees. Plates and stars again form near 5 degrees Fahrenheit.

Simple Prisms
Snowflakes are not frozen raindrops (that is better known as sleet). They form when water vapor condenses directly into ice, which happens in the clouds. In their most basic form, snow crystals are hexagonal prisms like the sample, above, but other, more complex forms are famously possible.

Sectored Plates
The simplest sectored plates are hexagonal crystals that are divided into six equal pieces, like the slices of a pie. More complex specimens show prominent ridges on broad, flat branches.

Stellar Dendrites
Dendritic means "tree-like", so stellar dendrites are plate-like snow crystals that have branches and side branches. These are fairly large crystals and can be viewed with a magnifying glass.

Fernlike Stellar Dendrites
Sometimes the branches of stellar crystals have so many side branches they look a bit like ferns, hence the name. These are the largest snow crystals, often falling to earth with diameters of 5 mm or more.

Needles
Formed around 23 degrees Fahrenheit, these snowflakes look like small bits of white hair on your sleeve. Why snow crystal shapes change from thin, flat plates to long, slender needles when the temperature changes remains something of a scientific mystery.

Twelve-Sided Snowflakes
Sometimes capped columns form with a twist, so that two six-branched crystals form end plates that are rotated thirty degrees relative to each other. These kinds are also quite rare, but sometimes a snowfall will bring quite a few.

Rimed Crystals
Clouds are made of countless water droplets, and sometimes these droplets collide with and stick to snow crystals. The frozen droplets are called rime. All the different types of snow crystals can be found decorated with rime. When the coverage is especially heavy, so that the assembly looks like a tiny snowball, the result is called graupel.

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Photos courtesy of Kenneth G. Libbrecht

Original Source: Time

Official Site: SnowCrystals.com