http://weather.thefuntimesguide.com/2009/01/the_snowflake.php |
Snow crystals are single crystals of ice while a snowflake is one or more crystals stuck together. Water molecules create a hexagonal lattice that is formed when water vapor condenses directly into ice in clouds when the temperature is freezing or below. There are several factors that influence the shape of snowflakes: humidity, temperature, and air currents. Colder temperatures create more intricate shapes – sharper tips and more branching.
It is commonly believed that snowflakes are perfectly symmetrical. This is much more the exception rather than the rule. Snowflakes are generally lob-sided and irregular. Symmetrical ones just tend to be photographed more! Snowflakes always have six sides or six points due to the shape and bonding of the water molecules.
You’ve probably heard that no two snowflakes are alike. This is more or less true. No two snowflakes are exactly alike down to their molecular level, however it is possible that there could be two visibly matching patterned flakes at some time if the environmental conditions for their growth were the same, although that is hard to fathom. William A. “Snowflake” Bentley (1865-1931), a self-educated farmer, spent years photographing snow crystals, capturing more than 5000 during his lifetime. His first snow crystal was photographed in 1885. He never was able to capture the same snowflake pattern twice. Snowflakes come in all different sizes too. Guinness World Records lists the largest snowflake as found January 1887 in Fort Keogh, Montana with one allegedly measuring 15 inches wide and 8 inches thick! That must have been quite a snowfall to see.
Snowflake watching is easy to do. Take a piece of black construction paper and head outside to see what kinds of flakes you can gather on it. The black background really helps the flakes show up. Some snow days produce more interesting flakes than others so be patient. An inexpensive magnifying glass can really enhance this activity.
There are many different types of snow crystals, but the most commonly known ones are the stars, dendrites (my favorite), columns, plates, capped columns, needles and irregular forms. A quick internet search will yield images of these various types. See if you can group the snowflakes that you see into these categories. What’s your favorite type?
I find that a good snowstorm does wonders for my ability to write and read. Writer Nathaniel Hawthorne felt the same way. “Snowflakes” collected in Twice-Told Tales, 1837, is a wonderful read as the snowflakes come down. http://www.islandnet.com/~see/weather/arts/snowflakes.htm
Snowflake photographs used with permission of snowcrystals.com
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