Why is the sky blue?

sun not only gives us light and heat, but also to paint all around us in the rainbow colors of the spectrum. A ray of white light is really colorful, we know that at his reflection in a drop of rain, which has become a rainbow. Then why is the sky for the sun to choose exactly the color blue, not green, for example? Although it is very difficult to imagine a green sky. Earth is surrounded by a layer of air that we breathe. It is oxygen, ozone and carbon dioxide. This layer is called the atmosphere. The thickness of the atmospheric layer is about 500 kilometers. It contains the air we dyshim.

Air consists of the molecules in which light can not be reflected. He scattered them. The electrons in the molecule falls under the influence of the incident sunlight to them and begin to emit. And the light is scattered at the same time. And this scattered light we see from Earth. Gases in the air, divided light on the known colors of the spectrum. We know them well know - red, orange, yellow, green, blue, indigo, violet. But the sky, we most often see blue or blue. Why is the sky blue?

Here comes into force a law of dispersion, an open Rayleigh, in which light with a wavelength less dissipated faster than light waves with a greater length. In blue, blue and purple colors of the spectrum wavelengths less. Therefore, it is their diffuse light we see in nebe.

Some colors of the spectrum with longer wavelengths, such as red and orange little scattered. At sunset, a layer of the atmosphere is increased many times over, the spectrum is more difficult to pass through it, and as the blue and blue paint were scattered, they have less celestial palette of colors in the evening, one color remains intact - red. Here it is what we see in the sky at sunset. And the sun itself appears to us then red. Of course, in other parts of the world at this point the sky is blue, there are short-rays scattered spectrum. In the morning the sun comes back to us, if he did not have to break through a thick veil of clouds and clouds. Then we see the sky in the clouds. But that's another story.

Source: po4emu.ru/index.php?id=42