Why is the sky blue? Somebody can tell me why it's blue

Sunlight looks white but is a combination of many frequencies (colors) of photons.

The higher frequency colors at the blue end of the spectrum are more energetic and scatter more easily. They are scattered by the atoms in our atmosphere and seem to come from all directions to reach our eyes.
The lower frequencies (red and orange) don't scatter nearly as easily.
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The phenomenon is called Rayleigh scattering. All of the light released by the sun has to go through the Earths atmosphere in order for us to see it. Light with the right wavelength can get "trapped in the atmosphere" the calculations and reasoning can get incredibly complicated but the basic idea is simple. Photons with a short wavelength can often hit gas molecules and bounce around in the sky, so much so that we see the sky as being blue as if was solid and blue as a blueberry. The other wavelengths of photons are either not visible to us or too large to often hit a molecule in the sky.

The larger the particles in the atmosphere are the larger the wavelength that is easily and regularly scattered, the same can be said about the amount of atmosphere that the sunlight has to go through this is why sunsets happen.

Rayleigh scattering and the size of of air molecule and atoms is the same as blue-green light - aquamarine. The atmosphere filters sunlight so the Sun seems to be yellow, but it's really white, by definition.

"...WHY IS THE SKY BLUE?
The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air.

However, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky. Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue. ...

....As you look closer to the horizon, the sky appears much paler in color. To reach you, the scattered blue light must pass through more air. Some of it gets scattered away again in other directions. Less blue light reaches your eyes. The color of the sky near the horizon appears paler or white. ..."

http://www.sciencemadesimple.com/sky_blu…



http://hyperphysics.phy-astr.gsu.edu/hba…

http://en.wikipedia.org/wiki/Rayleigh_sc…

http://en.wikipedia.org/wiki/Mie_scatter…

Oxygen molecules in our atmosphere scatter light, especially blue light. The sky glows the color of the scattered light.

Blue light is,scattered by molecules of air,so it appears to come from all directions