The atmospheric phenomenon, technically known as a circumhorizontal arc, only occurs at precise locations under specific conditions.

A rainbow is a spectrum of visible light ... A scientific tool that can do the same thing is called a spectroscope (early spectroscopes used prisms). You can make your own spectroscope by following ...

A rainbow contains all the colours of the visible spectrum. It is often possible ... Light is refracted when it enters the prism, and each colour is refracted by a different amount.

Rainbows don't actually exist. You can't find the end of a rainbow (or its attendant pot of gold). It's not possible to walk across a rainbow as the Norse gods did on the Bifrost, the bridge for ...

It is usually stated that Newton was the first to distinguish seven colours in the prismatic spectrum, but Maurolycus (1575) in the explanation which he gave of the circular arc of the rainbow ...