Recently, I’ve been waking up to some strikingly vivid sunrises. Unfortunately, by the time that I see the sunrise, get my camera, half stick my boots on and dash into the backyard, the colors have lost much of their vibrancy.
How do the colors disappear so quickly and what causes sunsets and sunrises to be there in the first place?
The colors of both sunrises and sunsets have to do with scattering. When light hits an air particle, the light waves bounce and scatter. Blue-ish violet is the shortest wavelength and is easily scattered by the numerous particles in the air. However, the human eye has a difficult time perceiving violet. This is why we see the sky as bright blue, not purple, during the day when the sun is right on top of us. The waves don’t have as far to travel to get to the rods and cones in our eyes!
Once the sun starts going down (or coming up), the sun is farther away from us and the light waves have to travel farther to reach our eyes. The greater the distance, the more molecules there are in the air. This causes the bluish-violet color to scatter and bounce so much that it bounces away and we lose it. The rest of the colors, like red, orange, pink, and yellow, wind up being what we see!
What’s amazing is that we on the East Coast of America are seeing the same sky as someone on the West Coast. The only difference is that (other than varying weather conditions) the wavelengths of light are traveling different amounts to reach our eyes. The blue sky doesn’t change into a pinkish sky – It’s our eyes missing out on the bounced blue light that the West Coasters are seeing. It’s almost as if we’re getting California’s “leftover” light waves.
So why do sunsets and rises come and go so quickly? Well, the answer is because the Earth bends A LOT. We may not realize in our day to day lives how circular our seemingly “flat” path is. The sun may seem to move more quickly once it reaches the horizon because the atmosphere is bending the light – the sun isn’t going down a flat plane.
Fortunately, once I get a good photo of the brilliance of the painted sky, I can have that with me even once the sun fully sets or rises and you can too! Explore what causes sunsets through art.