The reason snow appears white has to do with those beautiful natural artworks we call snowflakes. When it snows, “there’s a lot of traffic on the way down,” says Belles. The air, he explains, is riddled with tiny particles like dust, soot, and pollen. For a snowflake to form, a freezing water droplet attaches itself to one of those floating dust, soot, or pollen particles.

As that ice particle falls, more and more minuscule bits of water vapor freezes to it. Due to the way water molecules bond together when they freeze, a tiny hexagonal form begins to appear. And eventually, you end up with a beautiful six-sided shape we call a snowflake.

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Sunlight “emits all colors of the visible spectrum: red, orange, yellow, blue, green, indigo, and violet.” When these colors hit snow, each multi-sided ice crystal, or snowflake, scatters the colors like a tiny prism. All those colors shine equally in all directions, and our eyes, in turn, perceive all those colors colliding as white.

But why then does ice and snow look distinct, one clear and one white? “The difference between ice cubes and snowflakes is how light reacts with them,” says Belles.

“Sometimes with an ice cube, the light will be able to go straight through it. But with snow we’ve got this kind of broken mirror effect, with light bouncing off of all of those jagged edges.”

Probably a good question to ask my son to reason through once he understands the different ingredients making up the explanation...