Strange brights lights above Oakland ZooHusband saw odd light flash into clear sky high above Oakland zoo. Appeared to be very high in the sky and remained in a relatively fixed position. At first it appeared to be a thin line of reflected light but changed to more of a pinpoint after several minutes. Wife also watched after the first two minutes and both of the couple watched the light hover high in the sky above Oakland for about 30 minutes. During that time it moved position only slightly - drifting roughly north west. Two other lights appeared and approached the first light during the time it was hovering and then gradually disappeared by apparently moving higher into the atmosphere out of sight of the couple.Honestly, as wife did not see initial appearance of the light she was skeptical about the origin of the object in spite of the fact that it remained essentialy stationary high above the sky of the Oakland Zoo, suggesting theories of weather balloons, etc. as the origen of the light. However, after watching the object appear as a shiny stationary dot for approximately 30 minutes she was startled to see the light thin to a white line and then disappear in a bright flash. The entire event took place in a clear blue sky above a very active air space and normal planes with contrails passed far below these lights throughout the event. The sudden appearance and disappearance of the object as well as its apparent ability to remain stationary high in the sky was extremely unusual.