Earlier this week I was observing the gibbous moon, I noticed what looked like a burning ring of fire to the north of Plato. It turned out to be the crater Fontenelle. The whole rim of this crater was sunlit, giving a wonderful light show down here in Simpson Cross. The main body of the crater was on the terminator, further enhancing the effect of the bright ring.It was mesmerising, I had not seen this event before. This was approximately 6.00 to 6.30p.m. 18/12/07.... the moon was gibbous. I was outside again at 10.00p.m. the effect had lessened, the sun's rays had moved on slightly. As long as I time it right, hopefully in 28 days time +- I will see it again....