Why do stars appear to be white in color?

[RoughRoad]

Why do stars appear to be white in color when viewed from the naked eye?

 

[russ_watters]

Our color vision deteriorates at night, so most things you look at will lack color saturation.

 

[RoughRoad]

Still I am not satisfied with your answer. Can you explain in detail please?

 

[russ_watters]

According to a widely held theory of vision, the rods are responsible for vision under very dim levels of illumination (scotopic vision) and the cones function at higher illumination levels (photopic vision). Photopic vision provides the capability for seeing color and resolving fine detail (20/20 of better), but it functions only in good illumination. Scotopic vision is of poorer quality; it is limited by reduced resolution ( 20/200 or less) and provides the ability to discriminate only between shades of black and white. This limitation can be easily confirmed by noting that, at dusk, the different colors of a flower garden become virtually indistinguishable. However, the scotopic system provides enhanced sensitivity and low detection thresholds under markedly reduced illumination.

http://www.aoa.org/x5352.xml

 

[Vanadium 50]

You should take a look at Orion, where there is one bright star that is definitely bluish and another that is definitely reddish to the naked eye. But it's also important to note that the color of incandescent bodies at stellar temperatures is predominantly white: indeed, the red star mentioned above, Betelgeuse, has about the same color as an ordinary light bulb. Red stars are not fire-engine red.

 

[Borek]

Obviously they look white only to the naked eye...

 

[Chronos]

As Russ noted, human eyes tend to be monochromatic under low light conditions. If you walk into a dimly lit room you will notice colors are difficult to discern.

 

[Borek]

It is even more dramatic during full Moon. World often looks like made of mercury then, or something like that, shining gray. But when you try to take a picture, everything is in color.