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How does snow form?
Snow crystals form in clouds when the temperature
is below freezing. They are made by water droplets freezing
onto ice particles. As an ice crystal falls through the
cloud it bumps into others and becomes a snowflake. This
processing of bumping into others, along with some melting
and re-freezing helps to form their complex design. The
air that the snowflake falls through has to be below freezing
otherwise the snowflake will melt and turn to rain.
What do snowflakes look like?
Snowflakes are always six sided and it is thought
that no two are ever the same. The shape and form of a snowflake
depends on the temperature and amount of moisture within the
cloud. Snowflakes can be divided into six main shapes, plate
(flat), stars, column, needle, dendrite (lacy) and capped column.
When it is very cold the snow is very fine and powdery and the
snowflakes are quite simple in design, normally rod or needle
shaped. When the temperature is closer to freezing point (0
degrees Celsius), the snowflakes are much larger and more complex
in design, such as a star.
The Snowflake Man
An American photographer called Wilson A Bentley
spent much of his life looking at snowflakes and taking pictures
of them. He developed a huge collection of several thousand
photographs of snowflakes and was nicknamed 'The Snowflake Man'.
In 1925 he was quoted as saying: "Under the microscope,
I found that snowflakes were miracles of beauty; and it seemed
a shame that this beauty should not be seen and appreciated
by others. Every crystal was a masterpiece of design and no
one design was ever repeated. When a snowflake melted, that
design was forever lost. "
More
information on Wilson 'Snowflake' Bentley
Snow facts
It is recorded in the Guinness Book of World
Records, that the world's largest snowflake was 38 cm wide
and 20 cm thick. This occurred at Fort Keogh, Montana,
USA on 28 January 1887.
The tallest snowman ever made measured 34.63
metres and was made by residents of Bethel, Maine, USA. It took
14 days to build, finally being completed on 17 February 1999.
Nicknamed Angus, he had vehicle tyres for his mouth and trees
for arms.
Activity
Why not try making your own snowflakes
out of paper. Check out the art
section for more information.
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