Why is the sky blue?:cool:

If you look down at the bottom of this page, you will see that this question has been asked before on this site. I would suggest clicking on the link and seeing what the answers have been.

Rayleigh scattering - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Rayleigh_scattering)
Diffuse sky radiation - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Diffuse_sky_radiation)

Blue Sky - Why is the Sky Blue? (http://www.sciencemadesimple.com/sky_blue.html)

And that is only if you are not blue/green color blind in which case it could well be green.

And that is only if you are not blue/green color blind in which case it could well be green.

Sorry, what? It would still be blue.

Matter of view point, it is blue because you are told that shade is blue, if a person can not see blue, then its it truly blue to them. The idea that is it really a color if it can not be viewed in color, Or to animals that see onlyin black and white, is the entire concept of color merely a learned reaction to various shades or light. If green and blue looked the same to you, how would you know that the sky is blue and the grass is green.

Sorry in some deep thought today as to what is real and what is precieved by others as real

But the wavelength of the light is still in the region that we designate as "blue". I see no reason to bring in a specific observor here.