theguy on Nostr: The formulas might be the same (they are only an approximation after all), but ...

The formulas might be the same (they are only an approximation after all), but fundamentally ionosphere refraction is different. It literally reflects radio waves from some layer in the sky and sends them back at a specific angle. That could work on earth of any size and shape.

At the end of the day, this formula is only an approximation for a theoretical phenomena and does not by itself prove this phenomena exists in the first place. If optical refraction exists, it should be visibly demonstrable and easily repeatable in any direction be it vertical, horizontal, diagonal. The fact that one can reflect a radio signal from the ionosphere and bounce it back on earth to a large distance does not necessarily prove anything regarding earths size and shape, only that there is something up there in the sky that reflects the radio waves.