why sky is blue

The simplest question many of them get in their mind is why sky is blue? This is explained as the sky deals with deepest aspects of light which consists of weightless particles traveling at about 186,000 miles or 300,000 kilometers per second are called photons. We mostly find that the sky is in blue when the Sun is out.

The atmosphere around the Earth is largely made up of two colorless gases: oxygen and nitrogen as they are made up of atoms of about the same size. Red and blue light reacts very different from each other to oxygen. Because the wavelength of blue light is the size of an atom of oxygen, blue light interacts with the oxygen and is scattered by it, while red light, with its longer wavelength, goes right pass the oxygen atoms.

If the Earth had no atmosphere, the sun’s light which is a combination of light of a lot of colors would travel directly from the Sun in a straight line towards our eyes and we would see the Sun as a very bright star in sea of blackness. But because the Sun’s blue light is scattered by the oxygen in the atmosphere, blue light from the Sun enters our eyes from all sorts of different angles and we see the entire sky as blue. The atmosphere scatters violet light even more effectively, but our eyes are more sensitive to blue. Wherever we look towards the sky, some light is bouncing off an oxygen atom and entering our eyes, making the sky appear to be blue.

A more scientific way to explain why sky is blue is that the Oxygen and Nitrogen atoms are of a size that has a "natural vibration rate" (called frequency) that is closer to the rates of vibration of BLUE light. So the blue light can cause those atoms to start vibrating. The vibrating atoms then give off blue light when they stop vibrating, and that new blue light can go in any direction.

Sunlight reaches Earth's 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 tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time

To make it simple understanding about why sky is blue is when white sunlight passes through a lot of atmosphere the blue is scattered out of the beam leaving the red in the beam. This is why the sky is blue and the setting sun is red.

The scattering occurs at all wavelengths. Violet light is scattered more strongly than blue, but there is less violet than blue in sunlight so the sky is not violet.

Clouds include little condensed droplets of water. These droplets are a LOT bigger than atoms, and so they are not as transparent as oxygen or nitrogen gas. Therefore, ALL light colors tend to reflect off of those cloud droplets. During the day, that means that the light reflected off them appears bright white.

A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light.  When we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.