Disk shaped ufo above downtown Pittsburgh

I was waiting for a bus and I saw a weird light above downtown and I started recording it. It was still. At least as twice as high as the towers downtown. It was not from a blimp or a drone or anything like that but I don't know what it was. It was massive. There's a plane or helicopter flying under it in the video. I would have kept recording but my bus came and i had to get on it. The lights were going around it it was a massive disk just floating still. I have the video