If the degree of scatter is distance based then what explains the difference of the level of blue-ness between the sky when looking directly up and the sky when looking at the horizon.

The sky when viewed at the horizon would be thicker than the sky directly overhead. So more distance and subsequently more degree of blue! But this is not the case.

In the interests of expedience I offer a possible counter argument.

So the light at the horizon would have to be refracted at 90-degree angles to the observer while the light from overhead would require no refraction.

It may be that the intensity of blue light is also based on the angle of the light entering the sky.

Hmm!!!

Only true if the SUN is directly overhead. Even when the sun is on the horizon the sky looks bluer overhead than at the horizon. In fact the opposite horizon looks bluer than the horizon with the sun. This would imply a 180-degree refraction of the blue light.

Ok so lets progress the argument!

NEXT!!!

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Walter Zambotti