Which optical phenomena causes the sky to appear blue?

Question

Which type of optical phenomena would best explain why the sky is blue? Reflection, Refraction, Diffraction or Interference? Why?

I think it might be refraction. I don't want to hear about Rayleigh scattering I already know about that.

Answer 1

It's not refraction. It's largely Rayleigh scattering, sorry, with Mie scattering contributing.

From http://en.wikipedia.org/wiki/Rayleigh_scattering :

"Rayleigh scattering of sunlight in clear atmosphere is the main reason why the sky is blue: Rayleigh and cloud-mediated scattering contribute to diffuse light (direct light being sunrays)."



From http://en.wikipedia.org/wiki/Diffuse_sky_radiation :

"Scattering and absorption are major causes of the attenuation of radiation by the atmosphere. Scattering varies as a function of the ratio of the particle diameter to the wavelength of the radiation. When this ratio is less than about one-tenth, Rayleigh scattering occurs in which the scattering coefficient varies inversely as the fourth power of the wavelength. At larger values of the ratio of particle diameter to wavelength, the scattering varies in a complex fashion described, for spherical particles, by the Mie theory; at a ratio of the order of 10, the laws of geometric optics begin to apply."

Answer 2

The reason for blue sky is Rayleigh scattering nothing else.

Answer 3

Hiya Pal, It sounds like wisps of clouds left behind.

Answer 4

Because of the nitrogen content in the air



Hope this properly answers your question



Guru

Answer 5

It is due to Mie scattering.