• @[email protected]
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    15 months ago

    The sky is not emitting light, it is refracting light, like a prism. A blue LED is emitting light at different wavelengths than the blue of the sky.

    • @[email protected]
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      15 months ago

      … no shit.

      Like a prism, it affects all wavelengths. If it was “specifically that wavelength,” “not the rest of it,” it would be monochromatic. Like an LED. But it’s not. Rayleigh scattering diffuses any near-visible photons, at a rate proportional to their frequency, squared, squared.

      That’s why cooling paint works differently than merely reflecting light. Even red light can scatter in the air and warm up the environment. Red scatters less than blue… but infrared scatters less than anything visible.

      • @[email protected]
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        15 months ago

        Alright, I’m trying to say that “mostly transparent” is a fine way to describe it.