In skies that contain many ice crystals, sunlight gets refracted, and the sun shows a halo. Slightly rarer are “sun dogs” or “sun pillars”, patches and pillars of light surrounding the sun at regular distances. I first saw this during fieldwork in Kytalyk, Siberia, and since I had no internet connection there I had to wait for weeks before I could google what I had seen. A few years later during the polar night on Svalbard, I found out that the moon can do the same tricks if it is bright enough.