Green exists between blue and yellow on the rainbow. It’s odd think that the rainbow might be a few kilometres away but the green is only a colour of the light with a 495–570 nanometre wavelength. It isn’t possible to be sure how far away a rainbow might be because it really only exists in your head. The rainbow is dimensionless, having no weight, size or physical manifestation. Your eye is what receives the rays of light refracted by the millions of droplets of water as they fall from the sky. Transience amplified. But the green is real.
