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?
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.
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?
Not normally. In physics the general convention is to use photon energy. This puts Radio and IR ‘below’ red, and UV ‘above’.
That makes sense. Might’ve just been an accidental swap. Tweets aren’t peer reviewed.
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.
Oh shit, I hadn’t thought of that! That would be more accessible to the uninitiated, which is his thing.