As I was slipping and sliding on the road on my way to school this morning, I was painfully reminded that winter is here. It has been so unusually warm in New Hampshire that I had forgotten to put snow tires on my car. The ice on the road and my windshield were making some interesting patterns that made me think of the story I would read every year in engineering school when it started to snow.
The story was about Wilson Bentley, a photographer from Vermont who was the first person to photograph snowflakes up close. At nineteen, he made a mechanism to attach to his camera and observe the microscopic structure of snowflakes. This was in 1885, and over the course of his life up until his death at 66, he photographed over 5000 snowflakes. His works were published when he died and contained more than 2,000 of his best works.
The first time the shape of snowflakes was ever studied was in 1611. Johannes Kepler was the first person to think that the pattern of snowflakes could be the same as flowers. He was entranced by the symmetry of both snowflakes and flowers.
After Wilson Bentley photographed the snowflake, the interest in snowflakes turned scientific. In the 1930s, Ukichiro Nakaya began to try and grow snowflakes in a lab. This was much harder than he expected because of how natural snowflakes float freely as they form. To produce snowflakes so close to the natural state. To recreate this, he grew the snowflakes on a piece of rabbit hair. This allowed him to let the snowflakes form as they would in nature.
We can recreate a very different kind of ice crystal formation.
The Experiment
Materials
Bottled water
Glass or ceramic bowl
Plastic tray or shallow metal cookie sheet
Ice cubes
Freezer
Steps
Put water bottles in the freezer for two hours. Lay them on their sides for the best results, and try not to dent them.
Remove the water bottles from the freezer before they freeze. You’ll know they’re ready when crystals form when you shake the bottles.
Place a ceramic bowl upside down on a tray to catch the water overage.
Place an ice cube on top of the bowl.
Then SLOWLY pour while instant ice forms!
This is an example of flash freezing. When the very cold water molecules from the water bottle hit the freezing ice cube on top of the bowl, the water molecules get that little bit of a temperature drop they need to freeze. The ceramic bowl helps keep the temperature down and concentrated around the ice cube.
https://onlypassionatecuriosity.com/instant-ice-science-experiment-for-kids/
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