Sun dogs, also known as mock suns or parhelia, are optical phenomena that appear as bright spots of light beside the sun at an altitude of about 22 degrees. Another synonym for sun dog is a 22-degree halo, named after the angle at which the phenomenon occurs. The scientific term for sun dogs is "parhelic circle," which refers to the circular arc of bright spots around the sun. In some cultures, they are called "pillars of light" or "ice halos." In Finland, they are referred to as "revontulet," meaning "fox fires," while in Norway, they are known as "solhunde," meaning "sun hounds." Regardless of the name, sun dogs are a breathtaking phenomenon that has fascinated humans for centuries.