night-time contrails

Merlin has obviously been down in the village again as there was one of my favourite fog types well up into the valley and which, height-wise, finished just below our house. It looked like a sea, almost solid as if you could have run across it. At the same time the sky above was crystal clear with only a few stars and something I have never seen before, night-time airplanes leaving contrails which were illuminated by the unusually bright crescent moon which had a double halo around it.