Hovering objectCircular object with light around it. The object didn't make any sounds, it was bouncing up and down and moving from left to right in microseconds. Lights around the object were amber or orange. The object remained in the same location, then in an blink of the eyes, it disappeared. Clear sky we can see the stars but the object was covering some of the starts behind it. We had never seen something like that. We think that the object was about 20 thousand feet, the object did had any strobe lights or red ligh usually seen in an airplane. I have flying experience in a Cessna 172 and in a Piper Seneca II Twin Piston Engine. I have never seen an aircraft with that type of maneuvering capabilities.Whatever, we saw was huge in dimensions and disappeared very fast after hovering for 20 minutes or more.((NUFORC Note: Witness elects to remain totally anonymous; provides no contact information. PD))