Did you know the tale of Rudolph the Red-Nosed Reindeer is based in science? Well, it is! Do you remember the line in the classic Christmas song, "Then one foggy Christmas Eve, Santa came to say, 'Rudolph with your nose so bright, won't you guide my sleigh tonight?'"

Have you ever wondered why Rudolph's nose was red instead of blue or green or white or yellow (other than a good alliteration)? It's science! 

Light moves in waves, and the colors we see are all different wavelengths. The problem Santa was trying to solve on that fateful Christmas Eve was fog. When you drive through fog, you have to use the low beams on your car because the brighter lights (usually white or blue on cars) don't travel through the fog helping you see the road in front of you.

Image: NASA

Notice on the chart above from NASA how all of those brighter colors are on one end of the spectrum and red is on the opposite end. The wavelengths for blues/purples/whites are shorter than the wavelength of red light. The longer the wavelength the less the light is scattered by the particles in the atmosphere. This is also why red is used for "danger signals" like the blinking lights on tall towers to warn planes of an obstruction.  Red light can make it farther than any other color on the visible spectrum. 

Santa needed to find a red light to give him the best view in the fog, and luckily he had Rudolph's red nose to guide the way!