Brilliant white spheres above south fortuna mountain in San Diego.I and a friend went down to San Diego's Mission Dam area for a walk because it was such a beautiful day. The sky was unusually blue and clear with occasional white clouds. The sighting occured in the Mission Dam park itself. We were standing at the side of the paved road facing northwest, about 1/2 mile north of the visitor center, looking up towards south Fortuna Mountain. We were feeling kind of lazy and were just gazing at crows as they flew from the top of Fortuna Mountain down near the bottom of the canyon and back up again. After a while we were just looking around and noticed that the crows seemed to have left. I looked around for them and noticed that they were circling at the top of south fortuna and pointed it out to my friend. We were both looking at them and then I said "look seagulls are circling above them" realizing that they were not seagulls! My friend then said "those aren't seagulls" We were looking at about 8 brilliant white spheres doing circles and right angle turns at various hights up to about a mile high or so. They were obviously not birds, but the crows were circling under them which was really strange. We watched them in awe for about 45 seconds and then they were just gone in an instant! The crows were still there though. We stood there for a while hoping they would come back but they didn't after an hour had passed, while we talked about them. I didn't take any pictures because I didn't have a camera with me.