Why aren't there any green stars?

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Why are no stars green? Or purple? Or pink?

The stars are a quantum black body and the color they show is purely a function of the surface temperature. The hottest stars are blue and white. The coolest are red or do not shine (brown dwarfs).
Our sun has a good part of energy in the green, but also in the yellow. Its surface temperate is around 6000 /degrees Kelvin.

ruveyn

I thought maybe this could be interesting: Blue Stars.

The sun is actually white. It appears yellow from the ground at noon because of atmospheric scattering of blue light. There are no green stars because the appearance of green or any particular color but red or blue requires radiative selectivity that can't be achieved by blackbody radiation. Roughly, increasing temperature cycles through reddish, white-ish, and bluish.

I still love Master of Orion's description of Brown Dwarf stars (which are a real thing.)

"Brown Stars are really cool! So cool, in fact, it may be millenia before we have the capability to describe these bundles of joy!"

The reason we do not see green stars is the very reason the sun does not appear green. Colors are actually different wavelengths of light. Our sun's maximum power output is in the green part of the electromagnetic spectrum. That is to say, our sun emits the green wavelength the strongest. However it also emits all other wavelengths, and green is in the middle of the visible light spectrum. Imagine an archway of colored stones and green is at the top as the key stone. Yellow and blue are the stones on either side of green, and while they are not as high, they are about the same height with respect to each other. In other words, yellow light and blue light are emitted with roughly the same intensity, with yellow being emitted a little more than blue, and orange and indigo are emitted at a weaker intensity than yellow and blue light, but at roughly equal intensities with respect to each other, and then red and purple are emitted with the least intensities in the visible range, but still roughly the same intensity with respect to each other. So the green color is diluted due to the near equal intensities of light of other colors, and when you mix all of the visible colors of light you get white.

The same is true of other starts. Since they are broad spectrum emitters, the coolest stars will appear red to us in the visible spectrum, the hottest stars will appear blue, and everything in between will be muted and appear as orange, yellow, or white.

Here is a link with a more coherent explanation.
http://solar-center.stanford.edu/SID/ac ... enSun.html

Hold out a prism in sunlight... you will see all the colours within the visible spectrum that the sun emits.

They are all there but the energy distribution over the visible frequencies is not uniform.

ruveyn