Why Does The Sky Turn Red At Sunrise And Sunset?

General News | Sep-29-2020

Why Does The Sky Turn Red At Sunrise And Sunset?

The color of sky is an exciting phenomenon. At sometimes it appears blue while at other times it appears white or even red. But have we ever questioned ourselves that why is it so? Well, the main phenomenon behind reason this is the scattering of sunlight by the Earth’s Atmosphere. The atmosphere of Earth has particles smaller than the wavelength of visible light and therefore it is efficient in scattering light of shorter wavelength at the blue end than light of longer wavelength at the red end.

Yet again a question arises that why does sky appears red to us if the atmosphere scatters blue light more strongly than red? The reason behind this is that during sunrise and sunset the sun is near the sun. The sunlight must travel the greatest distance through atmosphere to reach us. During this long journey of sunlight, most of the shorter-wavelength blue color is scattered out and away from our line of sight. So, the light reaching us directly from sun appears red. Due to the same reason the sky surrounding the rising sun and setting sun also appears red.

Similarly, the sky appears white to us during afternoon as the sunlight must travel a smaller distance due to which there is less scattering of the different components of light and sky appears white to us. From the above arguments we get to know, that even a simple phenomenon such as the color of sky has so much science behind it. Therefore, we must think that how much science is behind our successful survival in this world. 


Class: 9  

Seth Anandram Jaipuria School