• Septimaeus@infosec.pub
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    4 个月前

    Also it’s interesting that NDT orients his EM spectrum by wavelength rather than frequency, such that “above red” and “below UV” falls outside the visible range. Is ascending wavelength the convention in astrophysics?

    • Little_mouse@lemmy.ca
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      4 个月前

      I imagine that he is equating the spectrum back to the rainbow, where red is the ‘top’ of the visible arch when a single rainbow is seen from the ground.

      Of course the outer ring from a double rainbow flips the order of the colours, but that’s probably being needlessly pedantic.

      • Septimaeus@infosec.pub
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        4 个月前

        Oh shit, I hadn’t thought of that! That would be more accessible to the uninitiated, which is his thing.

    • cynar@lemmy.world
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      4 个月前

      Not normally. In physics the general convention is to use photon energy. This puts Radio and IR ‘below’ red, and UV ‘above’.