Tried to capture this unusual effect of light and ice crystals in the sky. The images aren’t the best as I was a passenger in a car at the time. Took these out of the window. I’ve since learned that this phenomena is called circumhorizontal arc or “fire rainbow”. At least, that is what it appears to be. It is hard to covey the full effect with these photos, as the clouds were in constant motion. I did question the circumhorizontal arc theory because cirrus clouds don’t seem to be involved. They looked far more like cumulus or stratocumulus clouds. Maybe this effect is simply “cloud iridescence”. Not sure how to tell. Regardless of what it is called, it was truly beautiful and a lovely way to end the day.