This is something I have never seen or heard before, but from the air, or high up, rainbows are seen as perfect circles.
Most of the footage in this short vid is nothing short of "Spectacular" to look at. A guy posted this as a Mandela Effect but I can only say that I'm just surprised that I have never seen photographs or video of this phenomenon brandished about before. You would think it would be more popular? Perhaps I just need to get out more.
Anyway, well worth a look.