Welcome to brain Stuff, a production of I Heart Radio, Hey brain Stuff, Lauren Bogle bomb here. One of the reasons that people love snow is that it coats everything in a blanket of dazzling white weather. Reporters will say that we might be getting some of the white stuff, and every December you're likely to hear the song White Christmas over and over again. But if you think about it, it seems weird that snow is white at all, since it's just a bunch of ice crystals stuck together. So
where does it get its distinctive color. To understand where this whiteness comes from, we need to back up and look at why different things have different colors. In the first place, visible light is made up of many different frequencies of light. Our eyes detect different frequencies as different colors, and different objects have different colors because the particles that make up the object, it's atoms and molecules, react differently
to different frequencies or colors of light. The molecules and atoms absorb a certain amount of light energy depending on the frequency of the light, and then emit this absorbed energy as heat. This means that any given object absorbs certain frequencies of light more than other frequencies. A couple of different things can happen to the light frequencies that are not absorbed in some material. When a particle re emits the photons, they continue to pass through to the
next particle. In this case, light travels all the way through the material, which means the material will appear to be clear, like a flat piece of glass. However, in most solid materials, the particles re emit most of the unabsorbed photons back out of the material, so that no light or very little light passes through and the object
appears opaque. The color of an opaque object is just the combination of the light frequencies that the objects particles did not absorb, though the re emitted light can be to stored it on the way out, and that is why although ice is mostly clear, snow is mostly white. Let's back up again and look at an individual piece
of ice. Ice is not transparent. It's actually translucent. This means that the light photons don't pass right through the material and a direct path the materials particles change the light's direction. This happens because the distances between some atoms and the ice is molecular structure are close to the height of light wavelengths, which means the light photons will interact with those structures. The result is that the light photons path is altered and it exits the ice in
a different direction than it entered The ice. Snow is a whole bunch of individual ice crystals arranged together. When a light photon enters a layer of snow, it goes through an ice crystal on the top, which changes its directions slightly and sends it onto a new ice crystal, which does the same thing. Basically, all of those crystals bounced the light all around so that it comes right back out of the snow pile. It does the same thing to all of the different light frequencies, so all
colors of light are bounced back out. The color of all the frequencies in the visible spectrum combined in equal measure, is white. So this is the color that we see in snow, while it's not the color that we see in the individual ice crystals from that snow. Today's episode was written by Alice in mould Our Milk and produced by Tyler Clang. For more on this and lots of
other colorful topics, visit how stuff works dot com. Brain Stuff is production of iHeart Radio or more podcasts My heart Radio visit the iHeart Radio app, Apple Podcasts, or wherever you listen to your favorite shows.