I was at bus stop with my mother, when I heard a strange crackling noise in the sky opposite where we were waiting.
Coming from behind a cloud, about 20' above a house, was a slow moving green disk about 12' in diameter with a crackling orange revolving outer like a large pin-wheel wheel firework.
It was not metallic, literally just a green color.
It was ascending slightly.
I saw it first & pointed to it, asking what's that?
We both watched it for about 20 seconds, before going into thick cloud.
I looked about to see if anyone else was about, but nobody was around.
I said to my mother shall we ring the Liverpool Echo, a newspaper, & tell them what we saw.
My mother replied no they would not believe us.
A few years later, I read an article, that said if you ionize the atmosphere, you create a vacuum.
It brought back memories of what I had seen, & was a possible explanation for the orange revolving outer part.
It might well have been ionizing the atmosphere, creating a vacuum to enable propulsion?