Why do we see the color of the sun's light as red or orange, while we see the moon's light as white, although it's reflected from the sun?
[Physics] Why do we see the sun’s light color different from the moon’s light color
moonreflectionsunvisible-light
Related Solutions
[Physics] Why does a glass window reflect white objects white from an atomic scatterers’ viewpoint
The amount of reflected light is predicted by Fresnel's equations. The equations are a little cumbersome, but they tell you that the fraction of light reflected depends on the index of refraction of the two materials, as well as the angle of incidence.
One thing though, is since the index of refraction changes with the wavelength of light, then the amount of reflected light also changes with the wavelength!
Realistically though, the index of refraction barely changes at all over the visible spectrum.
In this image, the orange band is the visible spectrum. Those materials labeled "crown" are different types of glass. The range of the index of refraction for these glasses is only about 0.02 or 0.03 over the visible spectrum.
In other words, the glass barely notices the different colours. It reflects all visible light almost identically.
This is due to Rayleigh scattering, i.e. the shorter wavelengths (those near the violet end of the visible spectrum) are more deflected by dust particles than the longer wavelengths (those near the red end of the visible spectrum).
When the sun is near the horizon, it the path of the light through the atmosphere (and in particular through layers which have a higher concentration of dust particles) is longer, thus the scattering away of the non-red components is more pronounced.
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Best Answer
The light of the moon is a reflected light, and thus displays the type of surface on the moon in its spectral composition.
On the other hand the red orange of sun is seen through clouds or low in the horizon from secondary interactions. When overhead it is yellow and if behind clouds sometimes white . Part of the difference in the colors we perceive is also due to the much smaller amplitude of the light of the moon.We can look at the moon directly, not at the sun.