Now I know that rainbows are formed due to refraction of light from the sun hitting raindrops and light waves leave at varying angles between 40-42 degrees or somewhere around there. Also, that they’re round.

What I don’t understand is how it’s consistent, like I assume it’s hitting many raindrops, but all these drops are in different places so why does it still form a nice circle. Furthermore, why isn’t the whole sky a rainbow if it’s raining and thus hitting all the drops. I suspect the angle of the sun is playing a part but I’m not a science man.

Please help me get this thought out of my head.

  • @[email protected]
    8•5 months ago

    Not an expert, but here’s my understanding:

    A beam of white light contains many wavelengths. If it hits something that bends the light it causes the different wavelengths to bend at different angles. The light ends up coming out as a rainbow with each wavelength being bent to a different degree. Not all of these colours might hit your eye.

    If you have a whole bunch of prisms in the air, they all separate and scatter different colours of light in different directions. The red light from one prism might hit your eye but the other colours coming from that prism might not. The orange light from another prism might hit your eye but the other colours do not.

    A rainbow is a pattern created by red light from some prisms, orange light from others, yellow from others, etc. You only see one colour from one prism, but together they form a pattern. If you move the rainbow moves too. Prisms that were sending red light into your eye are no longer doing so. Others that missed your eye are now hitting it. The pattern stays the same but it’s being created by different prisms now.