It has to do with how the sun reflects off the atmosphere and what part of the electromagnetic radiation spectrum is being hit by light and reflected. That's why sunsets and sunrises are different than blue.
2 years ago
Last edited at 3:19PM on 10/15/2011
The Sun#039;s rays hit the Earth#039;s atmosphere, where thw light is scattered by nitrogen and oxygen molecules in the air. The blue wavelength of this light is affected more than the red and green wavelengths, causing the surrounding air to be blue.