There are 7.7 billion people live on earth approximately 770 crores. Atleast in minds of 700 crores people a question rises Why is the Sky blue in Color ?? and this makes it the World’s Most Asked Question. So lets dive in to the simple and easy to understand explanation.
You must have seen the light emitted from the sun appears so bright white to your eye, though it is a mixture of all 7 colors of the rainbow. We can take the example of a Prism, When white light passes through a it, the light get separated into its element colors – red, orange, yellow, green, blue and violet and this phenomenon is known as dispersion of Light.
To answer this we also need to know about free moving Particles in our atmosphere, they also play a role in making the Sky look blue. These particles are very small Molecules of Nitrogen and Oxygen. We know light travels in waves and they have varying wavelengths.
Some light travels in shorter waves and some in tall waves. For example Blue light waves are shorter than red light waves. As the Blue light waves are shorter they easily strike the tiny molecules moving in Air, and this leads to the scattering of light in different directions.
A British scientist in 1871 proved that Blue light waves in the Atmosphere are scattered 16 times more than Red light waves. But there is also a twist that is Violet light, it has even shorter wavelength than blue light, So why isn’t the sky purple or Violet?
Now our Eye also play a role in making the sky blue. Our eye sees what is easy to see and blue light is much easier for a human eye to see than seeing violet for example Violet color in a rainbow is less visible than other colors.
So now if we sum it up there are three things that play a role in making the Sky Blue:
1. White Light emitted from the Sun
2. Free moving particles and molecules in the Air that scatters light
3. Human eye likes Blue Color, hence the sky is Blue.
However the Sky color could be completely different for some animals like birds as their eye find ultraviolet easier to look.