It looked so cool that I took quite a few photos, but a) we were in a moving car and b) crappy BlackBerry phone and so the photos were all rubbish. I deleted them and thought no more about it.
But then I saw this photo on Tumblr and, recognising it as a “bit of rainbow”, clicked over and learned it’s actually a Circumhorizon Arc or “fire rainbow” and they’re really rare. In fact, this article says “If you are very lucky you may see a fire rainbow once or twice in your life.”
Fabulous. (Do a google image search – some of them are incredibly beautiful.)
So. Have you seen one?