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Richard Walker

Giant Stars

Visible to anyone in the world
Edited by Richard Walker, Tuesday, 12 Jan 2016, 00:42

In our stars we see red giants.

White and blue too.

Why no green ones?

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Me in a rare cheerful mood

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Stars: red, white and blue.
But also every other hue
That we are blind to.

The clue is that there are stars at one end of the visible spectrum, red, and starts at the other end, blue, but the others are white.  The problem is our eyes are of no use at differentiating colours when comprised of mixed colours of light.  For example, white LEDs appear white despite only emitting yellow and blue, or red green and blue.  Look at food or artwork under LED lights and the colours are all wrong because here is not a full colour spectrum there, merely just enough of a mix to fool our brain into thinking there is white light.

All those white stars are emitting light at different colours along the visible spectrum and some of them are indeed predominantly green.  But the Mark One Eyeball cannot detect that, we need a spectrum analyser to tell us it is there.