h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

any answers please

Because it would look daft it it were red Actually this has been asked before I'll see if I cna find the conversation thread, which had I seem to recall some plausible explinations

The sky is blue because light from the blue end of the spectrum is reflected whereas the other colours (red, orange, yellow, etc) pass straight on by. I think. Sounds right.

I don't think it's reflection. I believe that it is refraction, the same thing that creates rainbows. The sunlight is a mixture of colours, but something (water droplets?) in the upper atmosphere refracts it and the bit that points down to us below is blue bit. Also, the red sky at night/morning is light from the side so we see the red bit rather than the blue. Hope this helps

The hue of the daylight sky varies but it is typically composed of the shorter wavelenghts of the visible spectrum (blue being the short end and red the long end).What we see is the result of the scattering (selective scattering originally called Tyndall scattering or Rayleigh scattering after the scientists who did original investigations into the phenomenon.) Selective scattering occurs when light encounters particles smaller than its own wavelength. Short wavelengths are scattered significantly more than long ones. Air molecules are the primary scattering particles but when other particles are introduced to the atmosphere more intense and differently coloured effects can be observed. The bluest sky is usually directly above (depending on the sun's position) and the least blue at the horizon, where multiple scattering depletes the shorter wavelngths more. At the extreme sun positions (sunset and sunrise) the horizon becomes red because multiple scattering almost completely removes short wavelengths from light reaching our eyes.