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I read an article by NASA in which the following assertion was made:

The sun, in fact, emits light in all colors, but since yellow is the brightest wavelength from the sun, that is the color we see with our naked eye

Now, as a photographer, I was always taught that the light from the sun was brightest in GREEN and that is why green is the color to which our eyes are most sensitive. In fact, if we look at the spectrum of the sun:

solar spectrum

As we can see from this graph, the most intense light from the sun is not yellow, it is green. So, is NASA just wrong or what? Why does the sun appear yellow?

Qmechanic
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Ambrose Swasey
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http://solar-center.stanford.edu/SID/activities/GreenSun.html A link from Stanford which details what tfb commented. They Sun is not yellow, does not even look yellow except under certain conditions. It is full visible spectrum and is white if you choose to directly look at it in unfiltered and damage your eyes.

dlb
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Using some of the links in the comments and other research I have figured out the answer to the question.

The answer is that the apparent color for any source of light is due to the addition of the component light that makes up the spectrum for that source.

In the case of the Sun, it emits most strongly in the green-yellow-red part of the spectrum. If green is added to red, it produces yellow. The sun generates other colors as well, but they are overpowered by the energy of the green-red parts of the spectrum.

If we examine the spectral diagram from the question above, we can see that the area under the curve in the green-to-red sector is much larger than the area under the curve for the blue-violet parts of the spectrum. Therefore, it is the green-red part of the spectrum that is generating the net color.

Ambrose Swasey
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