Jason E. Andersen

Bonus fun fact: Sun Dogs, Halos, and Sun Pillars are one of the coolest things about winter. (See what I did there?) If you don’t already know, these are atmospheric phenomena caused by light reflecting off of ice crystals in the atmosphere. This reflected light creates optical effects in the sky. What effect you get depends on where the ice crystals are located.

Sun Dogs appear as glowing spots to the left and right of the sun. They’re caused by sunlight reflecting off of ice crystals suspended in cirrus clouds. Halos are complete rings of light surrounding the sun. Similar to Sun Dogs, they are also caused by ice crystals in cirrus clouds, only when the cloud is thin and overhead. Lastly, Sun Pillars appear as a column of light above (and sometimes below) the sun and are caused by ice crystals floating in the air itself.

Sun Dogs and Halos can be observed any time during the year, but these phenomena are more common during the winter because there are more ice crystals in the atmosphere. Sun Pillars only occur when it’s very cold and are the most uncommon of these effects. Sun Dogs and Sun Pillars are most commonly observed when the sun is close to the horizon, while Halos can appear at any time. Keep an eye out and see if you can spot them!

This bonus fun fact was spurred by me seeing a Sun Pillar on my way home during the arctic vortex. Below is a picture. It was really cool! (Ha! I did it again!)