What causes the different colours of a sunset?

The colours of a sunset are caused by the scattering of sunlight through Earth’s atmosphere. As the Sun sets, its light passes through more of the atmosphere, causing shorter wavelengths of light (blue and violet) to scatter away, while longer wavelengths (red, orange, and yellow) are scattered less and dominate the sky. This phenomenon is known as Rayleigh scattering. Additionally, particles such as dust and pollution can enhance the red and orange hues of a sunset, making them more vivid.