NPS

A sun dog at Denali National Park

Parhelions, more commonly known as sun dogs or mock suns, appear as fuzzy rainbows or bright spots in the sky "dogging" the sun. You are most likely to see a sun dog in the morning or afternoon during the winter. Records of this phenomena date all the way back to the ancient Egyptians. Famous Ancient Greek philosophers Cicero and Aristotle even made mention of sun dogs.

Mary McCormick

A sun dog

Sun dogs are the result of ice crystal clouds called cirrostratus clouds refracting or reflecting light from the sun. The clouds form a halo around the sun that interacts with sunlight. If light refracts through it, the sun dog shows a spectrum of colors. Red is a main color because it is refracted less than other colors. White sun dogs are caused by reflecting light. Sun dogs mostly appear when the sun is "near" the earth, or below a 61 degree angle relative to the horizon. Therefore they can only be seen around sunrise or sunset, unless you are in Alaska during the winter where the sun is always low in the sky.