A really hot day. Very few clouds in the sky. My wife went in to have a shower. I decided to swim in the pool to cool off at about 8:15pm. I took off my glasses. In I went. Floating on my back looking at the clouds thinking of the shapes they are making. These are Cirrus clouds. Wispy type of cloud. They sit at 23000+ feet (7000+m). The moon is in the south east sky but it still light out. The sun doesn't go down until about 10:00pm. There is really only 1 cloud formation in the east sky with it moving east. From my pool it was over my neighbor's house 2 doors east of us. It started out as a crab looking cloud that turned into a shark with an open mouth. I'm looking at it for about 5 minutes to see if it changes into something else. Out of the gills there is movement heading west. Nothing flew into the shark. It came out of the shark. At first I thought it was a plane but there was no jet stream. So I looked harder without my glasses. I need glasses for distance and details at a distance. The fact I can see this thing moving without glasses, it had to be BIG! It even looked like a plane as I could see what looked like the tail of a plane. It was cloud like silver/grey. As it moved west a bubble formed around the object. You could see the edge of the circle and the cigar like body with a tail but it was transparent between the circle and the main body. This showed up while it was over our house. The circle became more dominant as it went over the next door neighbor's house then disappeared over the neighbor's house 2 doors over to the west of us. It did not streak away. It vanished. Nothing. Invisible? It was just gone. I kept looking for it in the clear blue sky. Got out of the pool, put on my glasses and there was nothing but blue sky in the entire north and west sky. I don't know where it went and it did not disappear behind a house or tree or anything. There was nothing blocking my view. The entire sighting was around 15 seconds. I told my wife about this and she is freaked out about it. The next day we were out, looking at the sky and 2 different planes flew over. I took off my glasses and I can't see planes without them on. Therefore this had to be BIG or I couldn't see it.