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How is the light from the sun scattered by the atmosphere in such a way for us to see it as yellow when it is actually white?

Cort Ammon
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TECTEC3 Studios
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    Have you done any research? 5 second with google ("how light is scattered in the atmosphere") lead me to this NASA page. Does that help? If it doesn't, can you add more clarification to help explain what part of the process is stumping you? – Cort Ammon Feb 24 '17 at 20:54
  • To be fair, correct googling is "why sun seems yellow", led me to this page at Stanford – aaaaa says reinstate Monica Feb 24 '17 at 20:58
  • @CortAmmon That he didn't know the correct keywords for that. The terminology of "light scattering" isn't in the alpha memory of a layman. What doesn't surely mean that he was lazy to search. And also doesn't mean that you weren't right, I agree your comment. It only means that the SE network misses and educational physics site. – peterh Feb 24 '17 at 21:02
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    @peterh True. Then again, I also just had fun and copy/pasted the text of his question into google, verbatim. 3 out of the 5 top links answer the question (5/5 addressed atmospheric scattering in general). Moral of the story: googling physics questions is effective. Where SE excels is that, when the static pages of the internet confuse you about a topic, the Q&A format of SE is amazingly effective! – Cort Ammon Feb 24 '17 at 21:33
  • @CortAmmon I agree again. But it is not clearly communicated by the site to the new visitors. If it would be, they would be much fewer. | I've just tried to get the list of all symmetries of the Newtonian Mechanics. Also I can name most of them, but I was curious to the whole list. I needed it for a little enthusiast-level play with the Noether theorem. I didn't find this list. I think many OPs have similar problem, on their level. – peterh Feb 24 '17 at 21:38
  • -1. I agree with Cort : if googling the exact title provides an answer within the top few hits, it is a sign of lack of research effort. Too many users prefer to get other people to write a tailor-made answer for them rather than do their own searching. – sammy gerbil Feb 24 '17 at 21:40
  • @sammygerbil I agree in the help vampirism. But I think a possible goal of an SE site could be also a little bit more: between these top few hits should be at least a to the SE leading one. – peterh Feb 24 '17 at 21:45
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    Possible duplicate of How can sunlight be white , but pictures of the sun be orange? see also http://physics.stackexchange.com/q/189217/ – ProfRob Feb 25 '17 at 00:14

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Rayleigh scattering of light is responsible for the blue light from the Sun being scattered more than the red light.
The scattering is proportional to $\dfrac{1}{\rm wavelength^4}$.
As the light from the Sun passes though the Earth's atmosphere the blue light is preferentially scattered and so the light which is left produces the image of the Sun as being yellow or if it is low down near the horizon red because the light from the Sun has to travel through a greater thickness of the Earth's atmosphere.
The scattered blue light results in the blue sky.

Farcher
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Around a half of the Sun's radiation dissipates in the atmosphere. This happens more likely with blue photons as with the others. Generally, more energetic things interact more likely. In the specific case of the atmosphere, their refractive index is higher and the dissipation happens partially on the water molecules in the air.

The result is that we get back the missing blue part of the sunlight on the blue sky.

The summed light of the blue sky and the yellow Sun is exactly white. I can say really exactly, because this is the color (more exactly: photon energy spectrum) for which our eyes evolved.

peterh
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