Las Vegas Orbs display " V" ariel perfomance in early morning sky

My first ufo sighting occured in May 1987. Near Koval Lane and Tropicana Ave in Las Vegas, Nevada.  While entering my apartment complex, my friend and I saw nine cobalt blue with white halo orbs in " V " formation approached from the west at 12:30 AM. The spped being aprox. 10 mph. When noticing the strange group of lights made no noise and were thousands of feet high in the Nevada sky. They performed an aerial maneuver most aircraft don't dare try at the speed of instant happening.They collided into one large oval exploded in a fabulous firework with no noise. Joined again in the large oval and formed themselves into a diamond formation and continued their journey east over the casino skyline. When in the oval position, these nine objects moved around as if looking at tadpoles in an embryo. The sky was cloudless with a sprinkle of bright stars. Temperature around 90 degrees.
Illustration submitted with report.  Quite graphic.  PD