Disc (100 ft diameter) came out of cloud-hovered at altitude of 200 feet for 10 minutes. -15 people witness siting.Campfire meeting consisting of approx 15 people in the foothiils between Tucson and Oracle AZ on the west slope of foothills (just south of biosphere). Saucer shaped craft came out of singular cloud (clear night - no clouds) and hovered above campfire at altitude of approx 200 feet (very close). Dark colored material (not shiny) approx 150 feet in diameter. Around the outside of disc there was a perimeter tube seemingly to contain a series of lights that were tripped sequentially as though something was whirlling around inside the tude and tripped a light(s) as it went around. This silent vehicle stayed above us for approx 10 minutes and then flew away quickly and silently away. This vehicle was close enough to hit with a rock.((NUFORC Note: Witness indicates that the date of the event is approximate. PD))