3.7 Why Are There No Green Stars?

Pre-Lecture Reading 3.7

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See Cones.
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If a source of light is sufficiently bright, the human eye detects it with "cones."
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Cones measure the brightness of an object in three visible bands, roughly corresponding to red, green, and blue.
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The human brain then combines these measurements into a single color.
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Thermal spectra of increasing temperature result in the following combined colors: red, orange, yellow, yellow-white, white, blue-white, blue.
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Why not green?

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See Rods.
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If a source of light is too faint to detect with cones, the human eye tries to detect it with "rods."
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Rods measure the brightness of an object in a single visible band, not splitting the light three ways like cones do.
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The human brain interprets this measurement as a shade of gray, with white corresponding to bright and black corresponding to too faint to detect.
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The stars at night are incredibly colorful, but too faint to detect with your cones (with a few exceptions). Consequently, the night sky looks black and white to us. Too bad!

If aided by a telescope, the human eye can see red, orange, yellow, yellow-white, white, blue-white, and blue stars. Why are there no green stars?