CEDAR RAPIDS, Iowa (KCRG) - As the cold has now hit in full force, sundogs are becoming more common. Sundogs are formed when ice crystals are suspended in the air. This is usually a characteristic of an arctic or polar airmass. The sunlight is refracted, or bent, around these crystals and will focus light on either side of the sun, forming a bright blob of light. Red light is refracted the least, often giving these a reddish hue on the inner edges. These are most common at sunrise and sunset.
The technical term for this phenomenon is a parhelion, but “sundog” is more common. While the exact origin of the name “sundog” is unknown, the story goes that they are faithful to the sun, following it as it rises or falls, much like a dog is faithful to its owner.