(SciShow Kids intro plays)

Jessi: Who's up for a word game? When I say "science," what picture comes into your mind? Is it stuff like test tubes and telescopes? Maybe it's computers or microscopes, or living things like flowers or frogs. But did you think of anything that looks like... art?

A lot of science is really beautiful, and there might be no better way to study the beauty of nature than by looking at snowflakes. Have you ever taken a close look at snowflakes in winter when they land on your coat or mitten just before they melt?

Each snowflake is a six-pointed work of art, as cool and as individual as the ones you've probably made with paper and scissors. But how does nature make snowflakes? The first thing to know is, the little six-pointed pieces of ice that you and I call snowflakes are really made up of snow crystals. Scientists use the word "snowflake" to describe the fluffy white things that fall from the sky, which are actually bunches of snow crystals all stuck together. And the journey of a snow crystal begins in a cloud.

Up there, water in the form of gas called water vapor, freezes around a piece of dust or pollen that's just floating around in the cloud. This forms what's called a seed crystal, and seed crystals can become snow crystals if conditions inside the cloud are just right.

As the seed crystal bumps around inside of the cloud, lots of particles that make up water stick to it. The particles that make up water have a very specific shape, they kind of look like the letter V, and when enough of these particles stick together, they form shapes that have six sides, called hexagons, and that's your most basic kind of snow crystal.

But if there's enough water around, then more water particles will attach at the little points of that six-sided crystal, each becoming an arm or a branch. From there, all kinds of different things can happen. Even though all snowflakes have six sides, they can end up looking totally different from one another.

In fact, scientists have names for more than 30 different shapes of snow crystals. Some are big and flat and are called plates, others look long and narrow called needles. Still others are tall and wide like columns, and then there's probably the most famous shape called dendrites. They look kind of like stars that have sprouted tree branches.

The shape that each snow crystal takes depends on what the conditions were like as it formed in the cloud. Things like temperature and how much water's in the air can make a big difference if you're a snowflake.

So for example, colder temperatures often make flakes with more pointy and fancy arms, while snow crystals that are made in warmer temperatures and air with less water in it tend to be smaller and simpler. Now, you might have heard that no two snowflakes are alike.

A lot of them do look really similar to each other, but scientists think that it would be really hard for to to end up exactly the same. That's because the conditions in the clouds are always changing, so the flakes that they make are always changing too.

Once a snowflake takes shape, it's journey has only just begun. After bouncing around in the cloud for a while, it falls to the ground, and as it falls, it keeps changing depending on the temperature, the amount of water in the air, and other things like wind that it passes through.

Since each flake takes a different path all the way to the ground, each one ends up being slightly different. And that's why scientists say that no two snowflakes are exactly the same, but they're all really interesting and beautiful.

So now you know how snow crystals are made by nature, miniature works of art, no scissors required. Thanks for joining us on SciShow kids. And if you have a question, or just something you'd like to learn more about, let us know by leaving a comment below or emailing us at kids@thescishow.com, and we'll see you next time.

(endscreen)