Whats this large ring around the moon?
That is called a moon halo. It is made by moonlight reflecting off of tiny ice crystals high in the atmosphere. http://www.atoptics.co.uk/ If you think that is cool, check out this website, Atmospheric Optics. It has thousands of pictures of moon halos, sun halos, awesome rainbows, green and blue flashes, and much, much more. Enjoy!