green starlight
2007-Dec-12, Wednesday 10:11 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
mellowtiggerI've wondered before (and even asked an astronomy professor) why there aren't any "green stars". I didn't get a particularly good answer, though, so I've kept searching off-and-on for a few years. I finally located a good answer at a Cornell website.
http://curious.astro.cornell.edu/question.php?number=14
As anything heats up, it starts emitting light in a color (the peak, primary color anyway) that moves up the rainbow spectrum.
red, orange, yellow, green, blue, violet
Even iron in a forge (if it got hot enough) would do it. Those would be the colors, anyway, that could be detected by scientific instruments. The human eye/brain combination, however, sees something different.
red, orange, yellow, white, blue-white
These apparent colors correspond roughly to the spectral class that astronomers assign to stars to describe their temperature.
So, even if we're looking at an object hot enough to be "green" (our own sun is yellow-green (honestly!)), we'll still see it as "white" because so much light is also being emitted in the other colors. It's a lost cause, for the most part. We're simply unable to see "green-hot" objects, only "white-hot" objects. So if you ever look at artists' renderings of vistas on distant planets and the sun there is green, it's because something about the atmosphere on that planet filters out the other colors, leaving the non-green colors very dim when compared to the green light.
There ARE green stars (like our own sun), but we unfortunate humans are just unable to see them for what they are. *sigh*
http://curious.astro.cornell.edu/question.php?number=14
As anything heats up, it starts emitting light in a color (the peak, primary color anyway) that moves up the rainbow spectrum.
red, orange, yellow, green, blue, violet
Even iron in a forge (if it got hot enough) would do it. Those would be the colors, anyway, that could be detected by scientific instruments. The human eye/brain combination, however, sees something different.
red, orange, yellow, white, blue-white
These apparent colors correspond roughly to the spectral class that astronomers assign to stars to describe their temperature.
So, even if we're looking at an object hot enough to be "green" (our own sun is yellow-green (honestly!)), we'll still see it as "white" because so much light is also being emitted in the other colors. It's a lost cause, for the most part. We're simply unable to see "green-hot" objects, only "white-hot" objects. So if you ever look at artists' renderings of vistas on distant planets and the sun there is green, it's because something about the atmosphere on that planet filters out the other colors, leaving the non-green colors very dim when compared to the green light.
There ARE green stars (like our own sun), but we unfortunate humans are just unable to see them for what they are. *sigh*