The Sky is Blue: A Simple Fact Explained

The sky is "blue." This is a simple fact that most of us take for granted. But have you ever wondered why the sky appears blue? It's all thanks to a phenomenon called "Rayleigh scattering." When sunlight enters the Earth's atmosphere, it interacts with the tiny molecules of air, causing the light to scatter in different directions. Blue light, with its shorter wavelengths, scatters more effectively than other colors. As a result, we see a blue sky during the day. At sunrise and sunset, the light has to travel through more atmosphere, and the blue light is scattered away, leaving behind the warmer colors of orange and red.