194/365 October moon

I looked up the other night and saw this striking and unusual ring around the moon.

I've seen halos around the moon and sun before, but this one was really interesting.

I, of course, came back and did some googling about it. The most common answer to the question of what it's called is a 22° halo. They occur around the sun most often, but can occur around the moon as well.

But here's what I find puzzling and interesting: All of the sites I found that describe this optical phenomena mention that they have a tinge of red inside the halo.

If you look closely at this one, though, the red tinge seems to be on the outside of the ring instead.

I may have to do some further research to find out why. Or maybe it's due to our closeness to Halloween.

Creepy.

Camera: Canon 40D, 1/40s, f/4 at ISO 1600 at about 10:15 p.m.