Are There Green Stars? Exploring Unusual Astronomic Colors

[Scott S]

I was out in my backyard performing some astronomic observations for azimuth and latitude and was treated to a few of the recent meteors. I have seen a few different colored ones and it got me to wondering. I have heard of red, blue, white and other colored stars, but don't ever remember hearing about a green one.
So, are there any green stars?
And what other colors are missing?

 

[zhermes]

The color of stars are mostly just red white/yellow and blue; this is because they're very rough classes referring to the temperature (and therefore peak luminosity of the stars). Cold stars are red, moderate - white/yellow, and hot - blue. All of these stars appear fairly white (yellow with atmospheric effects) when looking at the entire visible band.

 

[turbo]

There are stars that are pretty green, but star colors are most evident in subjective comparisons, star-to-star. Loose clusters are great for this. The double cluster is a nice place to browse with a decent 'scope to identify various colors. One decent example of subjective color-perception is Alberio. The pairing of gold and blue stars is fairly striking when you see them together - either alone would be less remarkable.

 

[Jack21222]

There are no stars green to your eyes because those that peak in the green wavelength have a lot of other visible wavelengths also present near the peak. Your eye interprets this as white light, despite the fact that there are slightly more green photons than red or blue.

Phil Plait did a blog post about this.

http://blogs.discovermagazine.com/badastronomy/2008/07/29/why-are-there-no-green-stars/

 

[Antiphon]

The post is mostly accurate but a tiny bit misleading. You Do not need only green light to perceive the color green; you just need more green light than what is available from a blackbody radiator.

A great example of a natural spectrum that closely mimics the solar blackbody emission but looks very green is the sulpher plasma.

 

[Scott S]

Thank you gentlemen,
If the kids ever ask, I'll have this one covered.
Dad is looking smarter all the time.
...except to the wife, of course...

 

[Philosophaie]

There are also Orange stars such as Betelgeuse, Antares, Aldebaran, Arcturus and Pollux, all of which are clearly of orange or red hue.