If you live in Lowry Hill, you have probably seen Brandon Colpitts. He is the bald guy with binoculars, usually looking up and scanning the trees or the sky for birds.
If you ventured outside during the cold morning hours of Thursday, Dec. 4, you may have been treated to another quiet aerial spectacle, courtesy of the sun. Sun dogs, also known as parhelia or mock suns, appeared on either side of the rising sun, casting rainbow arcs above and below it and, when conditions are strong enough, forming a white halo known as a parhelic circle.
Like the aurora, sun dogs require just the right conditions. The sun must be low in the sky, and the air must be cold. Ice crystals in high, thin clouds lie flat, forming tiny hexagons that act like prisms. Their shape and orientation allow them to refract sunlight at a minimum angle of 22 degrees, focusing the light into bright spots at the same height as the sun. Because red light has a longer wavelength, it refracts less, which is why the inner edge of a sun dog glows red, transitioning outward through the colors of the rainbow.
Humans have been noticing and marveling at these celestial phenomena for thousands of years. Pliny the Elder was among the ancient writers who documented them. Shakespeare also referenced sun dogs in “Henry VI, Part 3,” casting the appearance of three suns as an omen of victory. He lingered on the image and barely mentioned the battle. Some things are simply more memorable.
As always, nature has more good news. There are also moon dogs. Getting outside at all hours of the day remains unbeatable. And if these moments teach us anything, it is to keep looking up.
