Rainbow

This evening, I saw one of the most beautiful rainbows that I have ever seen in my life.

A full double bow, and if you blinked quickly, there was the ghost of a third bow inside the main one.

Not only that, but the main bow had something I'd never seen before.  At the top (but not the sides) the inner colours were repeating.  There were three mauve bands, almost like ripples in the sand with a darker band inbetween them.

Does anyone know what could cause this?

Rainbow

Apparantly it was a 'supernumerary' rainbow.  That's a new one for me.  Caused by the wave properties of light as opposed to classical optics.  More information here: http://en.wikipedia.org/wiki/Rainbow