You probably have seen pictures of snowflakes, and heard that no two flakes are the same.
Have you ever wondered how scientists examine snowflakes? After all, most flakes are only a fraction of an inch across, and melt as soon as a person touches them.
Since 1940, scientists have had a clever way to study the structure of snowflakes, even if they can’t always study the flakes themselves. They spread a chemical compound over a glass plate and let a snowflake land there.
The compound immediately covers the flake and hardens. When the flake melts, it leaves behind a plastic case that shows its exact structure!