Four circular, oval light shapes in midnight sky flying in a repeated circular motion and converging at a centerpoint.My co-worker and I witnessed this phenomenon in the sky at Midnight this past Saturday night. I am the most skeptical sort of person about this type of thing so it's still really hard for me to believe what we saw. There were four circular, oval light shapes in the sky. They were flying in a repeated pattern in a circular motion, with absolutely perfect precision. They would then converge towards a centerpoint between them and then repeat their circular pattern.It looked to be an exercise of some sort. The precision was that of a machine or computer. The incident lasted 30 minutes. I was too dumbfounded to record it on my cellphone and am now really kicking myself for not doing so. Everybody I tell gives me a look like I'm really special.((NUFORC Note: Witness elects to remain totally anonymous; provides no contact information. PD))((NUFORC Note: Advertising lights. PD))