I was driving home tonight from a basketball game when about 9:15 pm I noticed a massive ring around the moon, shining through a thin layer of clouds.
This was in northern Wisconsin, Polk County. I was driving south on a back country road so I stopped on the road and leaned out my driver's side
window to snap this pic facing east. Where I am is a couple hours north of all the snow and rain weather across most of the country tonight. I know
the folklore says that a ring around the moon signals bad weather on the way, but in this case we're forecasted to stay nice all week (just above
freezing temps). But, like I said, the bad weather is just south of us.
In this pic, the ring appeared much brighter when I looked at through my camera review. After I downloaded, it's a little harder to see, but you can
see it there.
What causes a moon ring?
The ring around the Moon is caused by the refraction of Moonlight (which of course is reflected sunlight) from ice crystals in the upper
atmosphere. The shape of the ice crystals results in a focusing of the light into a ring. Since the ice crystals typically have the same shape, namely
a hexagonal shape, the Moon ring is almost always the same size. Less typical are the halos that may be produced by different angles in the crystals.
They can create halos with an angle of 46 degrees.
In the definition above it says that they are usually the same, but I've seen these many times but I thought this one was a little big. You can see
the field and trees in the far background at the bottom of pic, just to give you an idea how big the ring was.
Pretty cool anyways so I thought I'd share.