- Who
- Snow crystal in Cochrane, Ontario, on 30 Dec 2003
- What
- 10 millimetre(s)
- Where
- Canada (Cochrane)
- When
The largest individual snow crystal measured was 10 millimetres (0.39 inches) from tip to tip, as documented by Professor Kenneth Libbrecht (USA) in Cochrane, Ontario, Canada, on 30 December 2003.
Kenneth Libbrecht is a physics professor at the California Institute of Technology where he specializes in the dynamics of ice crystal formation. He founded the website Snowcrystals.com, a trove of scientific information and general trivia about ice crystals, in 1999 and has authored several books on the topic including The Snowflake: Winter’s Frozen Artistry, The Secret Life of a Snowflake, The Art of the Snowflake and Ken Libbrecht’s Field Guide to Snowflakes.
Although the words are often used interchangeably a "snow crystal" differs from a "snowflake"; a snowflake is actually an agglomeration of snow crystals that clump together to form a larger mass. A snow crystal is a single crystal of ice with the distinctive hexagonal (six-fold) symmetry (i.e., the shape most people typically think of as a "snowflake"). Owing to the slightly varied conditions in temperature and humidity etc that each crystal experiences on its journey from the cloud to the ground, no two snow crystals are exactly alike.
The largest reported snowflake was 15 inches (38 cm) wide and 8 inches (20 cm) thick, found by ranch owner Matt Coleman at Fort Keogh, Montana, USA, on 28 January 1887; he later described the flakes he'd seen as being "larger than milk pans" in Monthly Weather Review Magazine.
