On Friday, May 17, 2019, 10:55:25 AM PDT, \0xDynamite
   <dreamingforward@gmail.com> wrote:
   >I think you answered part of my question, which was partly didactic to
   force science to get more rigor in its explanation.  I think I will
   have to content myself with this because I know that rainbows and the
   sky being blue will NEVER be explainable by science.
   Mark
   No, the reason the sky is blue was explained long ago.  It's called
   "Rayleigh scattering".
   [1]https://en.wikipedia.org/wiki/Rayleigh_scattering
   Rayleigh scattering (pronounced [2]/ˈreɪli/ [3]RAY-lee), named after
   the nineteenth-century British physicist [4]Lord Rayleigh (John William
   Strutt),^[5][1] is the predominantly [6]elastic
   scattering of [7]light or other [8]electromagnetic radiation by
   particles much smaller than the [9]wavelength of the radiation.
   Rayleigh scattering does not change the state of material and is,
   hence, a [10]parametric process. The particles may be individual atoms
   or molecules. It can occur when light travels through transparent
   solids and liquids, and is most prominently seen in [11]gases. Rayleigh
   scattering results from the electric [12]polarizability of the
   particles. The oscillating electric field of a light wave acts on the
   charges within a particle, causing them to move at the same frequency.
   The particle therefore becomes a small radiating dipole whose radiation
   we see as scattered light. This radiation is an integral part of the
   photon and no excitation or deexcitation occurs.
   [end of quote]
   However, that explaination does not include a reference to what my
   understanding of Rayleigh scattering entails.
   Considered on the scale of the wavelength of the light involved, the
   density of air varies statistically.  Blue is a shorter wavelenth than
   red, so statistically that variation in air density is greater.  So,
   blue is scattered more than red.
   Blue sky means that more blue is scattered.
   Jim Bell

References

   1. https://en.wikipedia.org/wiki/Rayleigh_scattering
   2. https://en.wikipedia.org/wiki/Help:IPA/English
   3. https://en.wikipedia.org/wiki/Help:Pronunciation_respelling_key
   4. https://en.wikipedia.org/wiki/Lord_Rayleigh
   5. https://en.wikipedia.org/wiki/Rayleigh_scattering#cite_note-1
   6. https://en.wikipedia.org/wiki/Elastic_scattering
   7. https://en.wikipedia.org/wiki/Light
   8. https://en.wikipedia.org/wiki/Electromagnetic_radiation
   9. https://en.wikipedia.org/wiki/Wavelength
  10. https://en.wikipedia.org/wiki/Parametric_process_(optics)
  11. https://en.wikipedia.org/wiki/Gas
  12. https://en.wikipedia.org/wiki/Polarizability