Fun article
http://news.yahoo.com/s/livescience/20070121/sc_livescience/scientistmaybetwosnowflakesarealike
http://www.livescience.com/forcesofnature/070119_snowflakes_alike.html
http://news.yahoo.com/s/livescience/20070121/sc_livescience/scientistmaybetwosnowflakesarealike
http://www.livescience.com/forcesofnature/070119_snowflakes_alike.html
Snowflakes are created when snow crystals stick together. Some contain several hundred crystals. Scientists investigate how snowflakes form because of the possible influence they may have on global climate. In addition, researchers now believe ice crystals in the atmosphere, which typically are snow crystals too small to fall to the ground, play a key role in ozone depletion, possibly by acting as a catalyst to break down ozone.
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The exact form each snow crystal takes depends heavily on tiny changes in temperature and humidity it encounters as it falls, resulting in extraordinary diversity.
"It is probably safe to say that the possible number of snow crystal shapes exceeds the estimated number of atoms in the known universe," Nelson said.
Still, while "no two snowflakes are alike" might hold true for larger snowflakes, Nelson figures it might ring false for smaller crystals that sometimes fall before they have a chance to fully develop.
"How likely is it that two snowflakes are alike? Very likely if we define alike to mean that we would have trouble distinguishing them under a microscope and if we include the crystals that hardly develop beyond the prism stagethat is, the smallest snow crystals," Nelson said.
"Good luck finding them though," he added. "Even if there were only a million crystals and you could compare each possible pair once per secondthat is, very fastthen to compare them all would take you about a hundred thousand years."