Large triangular object with white lights along the side. Silent

I was driving along highway 429 South between Liberty and Siler City.  On my left, I saw a large (1/2 football field) sized triangular object with solid white lights going along the side.  The object was motionless above the trees  beside the road.  There was no sound.  I pulled off onto the emergency lane and stopped.  Noted that perhaps 4-5 other cars had slowed/stopped also.  Kept watching this object until it just disappeared.  One moment, it was there and the next, it was gone.