Sun Dog Days

There is always something to look at in the sky. Clouds are so variable that you don't really ever see the same configuration twice; rather, one altocumulus is reminiscent of another (i.e., "I saw a deck of altocu like that down the shore once in the 80s!"). Optical phenomena like rainbows, however, are always singularly unique; however, that might be a function of their relative rarity. The least rare of these around here are parhelia, or sun dogs, and they seem to pop up a lot on my drive home this time of year.

Sun dogs look like little patches of rainbows directly to the right and to the left of the sun. Red is on the sun-side of the sun dog, and blue is on the outside. They form in ice clouds, where hexagonally shaped ice crystals refract (bend) and diffract (separate white light into spectral colors) sunlight. All this science creates true beauty.

We were lucky enough to witness this incredible sight while on Mt. Rainier this past summer. Instead of the patchy sun dog we are used to seeing in New Jersey, this one was so elongated that each color of the spectrum was clearly visible. I smiled to myself as other tourists around us wondered aloud about what caused this to happen. Score one for atmospheric science, whether they knew it or not!