A couple of nights ago, I was in a pool, floating on my back and looking up at the sky, and I was pretty sure I could see where the light from the sun reflected off the moon stopped. I could see a very lighter black in a rather large circle around the moon and a darker black that began on the fringes of this lighter circle. So, my question is/are, was I hallucinating, and, if not, does light in any circumstance travel uniformly, or will some rays extend beyond others? This is barring something in the way of the rays, of course.

Hi Protagorus,
You seem to be describing an atmospheric phenomenon like a halo, caused by light cloud (light enough to be invisible in the night sky, except close to the moon)

Hey Protagorus!

The "halo" is caused by miniature ice-crystals in the atmosphere, which either refracts the light. A discussion about can be found at http://www.sciforums.com/showthread.php?s=&threadid=12386.

Thanks guys, that link really helped.