
Why can’t we reach the end of a rainbow?
Unfortunately that pot of gold is just joke played on you by the sun, the rain, and your own eyes.
Asked by: Tom Roberts, Liverpool
A rainbow isn’t a fixed object that hangs in the sky. It’s an illusion formed between the sunshine, the rain and your eyes. Light bounces out of the raindrops at an angle of 40° for red light, and 42° for blue. And that’s true wherever you stand, so as you move, the rainbow moves too and you can never catch it.
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Authors

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
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