20 feet long, metal object, hovering in air and then moved horizontally.

I was driving in my car and saw 1, metal object hovering above an intersection at Grand Ave and Randolph Ave, in Chicago.
This object was about 20 feet long. It looked like it was made out silver metal. It was shaped like a lamp post. It had a long metal pole attached to a megaphone shape object. This object was moving around in circles and when the megaphone shape object turned toward me; I saw large circular holes in the top of the megaphone shape. It looked like it was a device to record sound but in the shape of a lamp post.
I thought this item was possibly being pulled by a helicopter or a crane but this item was hovering/ floating on its own.
I turned my car around and followed the object for about 1/2 minutes. It started to move horizontally and get higher in the air. It started to move North/ East and I was unable to keep up with the object.
The object kept turning in circles and in no detectable pattern. There was no smoke emitted from the object.
I was able to get 2 short videos of the object.