This was really cool in-person. I didn't take the time to check my camera settings, so it didn't record as well as I'd have liked. I am calling it a crepuscular rainbow. This is a pic of sun beams (crepuscular rays) streaming through the clouds - into a mist of raindrops. So, this tiny section of the rainbow has spokes. A half-hour and 50km later, it faded away, and then shortly after, it's counterpart appeared in the other corner of the sky.