Halo Around The Moon

Spencer just came inside from taking Tank out for the last time this evening and asked me to come out to see something cool. It was cold, but I went anyway, because I like cool stuff. This freaked me out a little bit, but it was definitely cool. Apparently it is called a halo and it is apparently fairly common, though in all my 28 years I have never seen one. Maybe I just never paid attention. It occurs when conditions are right: high thin clouds containing millions of tiny ice crystals cover much of the sky and each of the ice crystals act as a miniature lens. Since most of the crystals are an elongated hexagon shape, light enters one side of the crystal and exits through the opposite side and refracts 22 degrees. And apparently sometimes, but more rare, it can refract in 46 degree halos and other even rarer degreed halos. I did my research...mostly to make sure the world wasn't ending or I wasn't about to get some super hero power.