Why can’t we reach the end of a rainbow?

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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