Sun dogs are beautiful atmospheric phenomena, creating bright spots on either side of the sun.

Sun dogs, also known as "parhelia," are bright spots that appear on either side of the sun, typically when it’s low in the sky. These optical illusions are caused by the refraction of sunlight through ice crystals in the atmosphere, usually found in cirrus or cirrostratus clouds. The ice crystals act like prisms, bending the sunlight at a 22-degree angle, which creates the characteristic halo or spot. Sun dogs are often seen in pairs, one on either side of the sun, and are most common in colder climates or during the winter months.

The science behind sun dogs involves the physics of light refraction. When sunlight passes through the hexagonal ice crystals in clouds, the light bends and splits into colors, much like the way a prism splits light. The 22-degree angle of refraction gives the sun dogs their distinct appearance, often accompanied by a halo around the sun. I personally witnessed this stunning phenomenon on a trip to Brighton, where the sun dogs appeared as bright, radiant spots beside the setting sun, making for a truly mesmerizing sight.

Photo attribution: Jnimens, CC BY-SA 4.0, via Wikimedia Commons