The reason behind – Sky Looks Blue
Amount of scattering is inverse of the fourth power of wavelength. Scattering of radiation of short wavelength is more. When white sunlight crosses the atmosphere, then violet, blue, indigo etc rays of short wavelength spectra are dispersed more by the floating dust particles in the air and spread around. Sunlight reaches earth atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered in all directions by the small molecules of atmosphere in Earth atmosphere. Blue is spread more than other colors because it travels as shorter, lesser wave. So, this is why “we see a blue sky most of the time “. Our eyes are sensitive to blue light, so scattering light from the sky, when enters into our eyes blue rays are predominant. So, the sky looks blue.
Some of the reasons why the sky is blue are:
- The light from the sun looks white. But it is really made up of all the colors of the rainbow.
- When white light shines through a prism, the light is separated into all its colors.
- Blue light waves are shorter than the red light waves.
So, when the Sun is high in the sky, blue light is spread in all directions as daylight passes through the atmosphere and we see the sky as blue.