Light is a wave and each of these colours has a different frequency and therefore a different wavelength of light. When light collides with gases in the earth's atmosphere the light is scattered.
Blue light has a short wavelength and scatters more than red light.
The light reaching our eyes from the sky is blue. At sunrise and sunset, sunlight passes through far more air before reaching us. File Seen from the side in a darkened room, the light beam from a projector appears blue, because of the smoke and dust in the air scattering the light. Resources and actions 1. Fill the bottle with water.