Friday, February 1, 2013

Snowflake Jewels

Ken Libbrecht, a physics professor at Caltech was originally trained as a solar astronomer, but in recent years his interest has focused on snowflake formation. Since we have been kids, we have been told that no two snowflakes are alike and Libbrecht's photos seem to confirm this fact.

Here are a few of the more than 10,000 that he has photographed. To see more, visit his gallery.

Dr. Libbrecht, who has written several books about snowflakes, tells us that snowflakes develop from single crystals of ice and can be either one snow crystal or groups of snow crystals that adhere as water vapour condenses on the surface. Snowflakes are always hexagonal and can develop arms and then new growths on the ends of the arms. The final result is always sixfold symmetric.

The formation of snowflakes is dependent on temperature and humidity. The crystals become more complex at lower temperatures until the humidity becomes lower at which point the strutures become simpler columns and plates. A temperature around -15C produces large stellar crystals. Conditions in Northern Ontario, particularly around Cochrane make it an ideal location to study snow crystal formation.

One thing I love best about snow is how it sparkles in the sunshine.