I am fascinated by meteorological phenomena. Not so much the -5 F (with -29 F wind chill) we’re experiencing right now, but, rather, the ‘hey, look up in the sky, over there,’ stuff. This morning, nature treated me with a sun dog. Two, actually, but I couldn’t capture both in the photo at the same time.
Sun dogs (official scientific name: parhelia*) are parenthetical rainbows that punctuate the sun. I think they are one of the coolest things to see in the winter sky. Especially on brutally cold days like today.
Warning: The following paragraph contains SCIENCE.
Sun dogs form when hexagonal-shaped ice crystals in cirrus clouds refract sunlight. The light is bent at a 22 degree angle by the horizontally aligned ice crystals, creating a bright beam of refracted light. A great visual explanation can be found on the U of I website. Parhelia can also be seen at night, under the same conditions, hanging around the moon (these are called moon dogs). If the orientations of the crystals become less ordered, a halo forms, which is also pretty cool, too. I took a picture of a moon halo in September 2012.
Whether or not you appreciate parhelia for their beauty, the science behind them, or a little of both, they are definitely a pretty amazing phenomenon. What is your favorite meteorological treat?
*Parhelia is plural. Parhelion the term for a single sun dog.