Why Is the Sky Blue? When we look at the sky on a clear day, we see it as blue. But why does this happen? The answer lies in the interaction of sunlight with Earth's atmosphere, known as Rayleigh scattering. Rayleigh Scattering: Visible Light Spectrum: Sunlight is made up of a spectrum of colors ranging from red to violet, each with different wavelengths. Interaction with Molecules: As sunlight passes through the atmosphere, molecules and atoms in the air scatter the light. Shorter wavelengths (