In the absence of a prism, what is making the photons in a rainbow congregate into bands of separate colors?

Question

And why are the colors are always in ROYGBV order?

In: 5

Answer 1

There is a prism – droplets of water.

These act to diffract the light into the visible spectrum.

The colours represent different wavelengths of visible light, with the higher frequency wavelengths at the outer rim of the circle (rainbows are circles, we only see part of them)

The only reason the colours are defined that way is because it was defined that way.