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Is there the effect of sun rising and sun setting, in terms of Rayleigh scattering and visual spectrum and other factors completely similar and symmetric? I mean can one recognise them from a picture taken from the sky?

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what is your avatar, a sunrise or a sunset? =) –  HDE Oct 3 '11 at 18:10
    
That is actually my question, sir. –  Peter Jones Oct 4 '11 at 18:47

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The average air temperature is always lower at sunrise, which changes the atmospheric refraction infinitesimally. On the moon, you would only have the tiny difference from the doppler shift due to your motion relative to the sun, so that sunrise would be a teeny-weeny bit bluer than sunset.

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In most areas yes, there is more atmospheric pollution generated during the day so sunsets are slightly redder than sunrises.

But from purely orbital/geometric measurements, no they are identical.

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I mean, say in a clean rural rural area, in natural situation, say 10000 years ago. I mean the natural phenomena. –  Peter Jones Oct 3 '11 at 6:30
    
@Peter - from a purely orbital/geometric point, no they are identical. –  Martin Beckett Oct 3 '11 at 12:59
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""I mean, say in a clean rural rural area, in natural situation, say 10000 years ago. I mean the natural phenomena. "" Even under Your "Muesli"- romantic conditions every morning and evening is different! At best one can speak about average mornings and evenings. BTW the looks of those rises and sets are made in upper troposphere and up, where manmade pollution is neglegible, whereas some vulcano eruptions made very beautiful sunsets for months. –  Georg Oct 4 '11 at 13:06

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