The Scattered Waves Above My House Were Pretty Last Night

Last night there was a warm glow waving through my window, so I went to the roof to find out what was going on.
The clouds were going on,
so was the sun,
and that whole scattering* of light through the atmosphere thing as well.

Being a photographer, I must look at it through a lens, so I looked at it through my lens.
Below are the results.

If you must know, those are the San Gabriel Mountains as seen from Pasadena.

*When the sun is directly above you, the sun’s rays traverse a relatively short distance through the dense parts of the atmosphere until they reach your eye. According Rayleigh model of scattering, blue light is scattered by small particles and gases in the atmosphere to create the blue sky we perceive. In the distance, Mie scattering of all the wavelengths of sunlight by larger dust particles or clouds creates a paler blue in the lower part of the sky. In the absence of an atmosphere, we would see a black sky.

At sunset, the sun’s rays have much farther to travel through the atmosphere to reach your eye – more than 30 times the distance at midday. This increased distance amplifies the effect of the Rayleigh scattering that makes the sky blue, so that the violets and blues in sunlight are lost. The light you see is missing the violets and blues… leaving you with various shades of yellows, reds, and even purples.

The immense variation in the colors of sunsets depends on the concentration of small particles, or very small aerosols, in the atmosphere. In the absence of these small aerosols, the sky at sunset takes on yellow or orange hues, while increasing concentrations of small particles in the lower atmosphere further increase Rayleigh scattering to shift the hues towards the red end of the spectrum.

[The above paragraphs are from this web page:
http://www.webexhibits.org/causesofcolor/14B.html]

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