Moon halo

Did u notice the night sky on Friday(12-sep-08)?
The sky was clear and the moon was unusually bright and it had a bright big ring around it.
Yes, you read it right!
Moon had a ring around it, and i was excited to see it.

I was pondering over the cause for such a rare phenomenon. I googled for it and came to know that its called moon halo and the explanation for the same is as follows:

Moon halos are caused by tiny ice crystals that have gathered twenty thousand feet above the ground, as thin, wispy clouds. These clouds are so thin, you might not notice them at night, if it weren't for their effect on the moonlight. Incoming light rays from the moon are bent--or "diffracted"--by these ice crystals at an angle of twenty-two degrees. This means that in addition to the direct moonlight, you will also see diffracted moonlight in a circle twenty-two degrees away from the moon. Like a rainbow, this halo can even be slightly colored; red on the inside, and blue on the outside.
For more info about moon halo, click here.

And here is the interesting part:
sight. Actually, a halo in winter doesn't have absolute significance; but during the warmer months, it usually foretells the coming of a thickening of warm air overhead; in most cases, a long, slow rain should eventually arrive in about 12 to 18 hours!!

Wow, thats indeed a great news !!