I'm going to try one last time.

There are three main ideas that we need to include to understand what color the sky will be seen by non-color blind humans.

1) How the human eye sees color

2) What wavelength distribution of light in the sky is available for scattering

3) The wavelength dependence of the scattering.

**How the human eye sees color**
The eye: I have used the x,y,z functions called the color matching functions

color matching functions
These functions are not really the eye's response to light like one might measure the response of a CCD detector. There is some freedom in their definition. To see this look at the following three integrals:

The key requirement is that for all possible

source functions there is a unique mapping into the

space. This uniqueness can be preserved for any non-degenerate linear combination of the of the color matching functions. This property was used to adjust the original color matching functions into the ones we use today. The original experiment resulted in the "red" color matching function having negative values. Now all the color matching functions are positive and the "green"

color matching function when multiplied and integrated gives a number that is proportional to human visual brightness.

Where

is the illuminate.

**What wavelength distribution of light in the sky is available for scattering**
The light available is simply the light from our favorite star which is almost a blackbody radiator. But what I have used is the measured solar spectra. In color science this is often called the

D65 Illuminate
I have updated this plot to show the colors associated with the wavelengths.

**The wavelength dependence of the scattering**
I will scale for intensities at the end, so now I just need the wavelength dependence of

Rayleigh scattering.

I have used:

to scale the minimum wavelength to one.

** Putting it all together**
Then I put it all together using the equations from:

Useful Color Equations
First I calculate the

color space values:

The last step is transforming the

color space values in to an RGB monitor color space. This is just a matrix transformation and should be done differently for all of our different uncalibrated monitors but I just picked a stranded off of the website linked to above.

I have made the blue color strip below that shows the range of blue one can get with just Rayleigh scattering at different brightness levels. Notice there is no purple.

Any reasonable rebuttal to this work needs to contain more than just weak words and silly colorful pictures. To show that Rayleigh scattering is not responsible for the blue we see in the sky I expect some math and references (via links). And if you can't do the math come back when you can.

P.S. The screen name of c186282 is a little "c" for the speed of light and the 186282 is the speed of light in the crappy units we use on this side of the ocean, miles per hour.

P.S.S Hey! I got math and silly pictures!