Disc-shaped UFO seen over Billericay, England

On April 11, 2019 at 19:37, a man was on a plane returning to England when he saw a disc-shaped UFO in the sky.

Witness report:

I was on a flight to heathrow airport in england and i saw a shiner disk shaped object outside the plane window. many other people saw it through different windows , so it couldn't have been a crack or light reflecting off of the window. it them moved up and down/ side to side so i could tell that it wasn't an aircraft.

Zoom into the original photo and you can see it. i also edited the other two photos to be clearer in showing the shape of the ufo.

http://ufostalker.com/sighting/99681, 12th April 2019