Sundogs, also known as parhelia, are bright spots that appear on either side of the sun, typically when it is low in the sky. They occur due to the refraction of sunlight through ice crystals in the atmosphere, often found in cirrus or cirrostratus clouds. These optical phenomena can create a halo effect around the sun, enhancing the appearance of the sundogs. Sundogs are most commonly seen in cold climates, where ice crystals are more prevalent. They can appear as white or colorful spots, depending on the angle of the sunlight and the size of the ice crystals. Observing sundogs can be a beautiful reminder of the complex interactions between light and the atmosphere.