On the night of August 18th, I was sitting with my mother and sister on my mother's back patio when we saw a formation of 10 or 12 extremely bright lights due east approximately 30º above the horizon. Each light appeared about the size of an aspirin when held at arm's length and the total formation covered a width of about 10 inches at arm's length. The formation seemed to twist on a central axis slightly then the lights on the outer ends suddenly and quickly moved towards the center in an arc movement, merging with the next lights in. Those lights then moved quickly and merged with the next ones; this continued sequentially until there was only one bright light in the center which then emitted a cloud of swirling, sparkling smaller and dimmer lights just as it disappeared. Our sighting lasted for about 8 seconds but the lights were already there when we saw them so they could have been there longer. It seemed to be extremely large, quite high, and fairly distant. All three of us witnessed this. These lights were definitely not fireworks; any fireworks close enough to appear that large would have been audible as it was a quiet night and there was no accompanying cloud of smoke. Three aircraft were also in the same quadrant of sky moving towards the area where the lights were but they were too high to identify. The aircraft did not appear to be in formation but were moving fast.My mother called the local sheriff's office to report it. The deputy she spoke to stated that a similar sighting had been reported the previous night. I also posted to a local facebook group and one other person replied that he had seen it as well. Additionally, the cat seemed very disturbed and climbed to a spot she had never climbed to where she sat staring in that direction for nearly an hour. Note: I grew up in this area and am accustomed to seeing maneuvers from Davis Monthan AFB being carried out over this valley; this was most definitely nothing like that.