Why Is The Sky Blue? Explained With Rayleigh Scattering

The sky appears blue due to a phenomenon called Rayleigh scattering. When sunlight enters Earth's atmosphere, the shorter blue wavelengths scatter more easily than the longer red wavelengths. This causes the blue light to spread throughout the atmosphere, making it appear blue to us. At sunrise and sunset, when the sunlight has to travel through more of the atmosphere to reach us, the longer red wavelengths scatter less, causing the sky to appear red or orange.