Pennsylvania, July, 1972

While driving home to Cincinnati from my bother's wedding at Westpoint, New York, in July of 1972, I was sitting in the back seat of my parents' car.  I looked out the back window and saw 3 large bright white glowing orbs.  
They were in the shape of a triangle, that is, one light at each angle.  They moved simultaneously in a clockwise, then counter-clockwise motion.  
I told my parents, they didn't believe me, of course.   When I looked back around, the lights/orbs were gone.  Has anyone reported a similar incident or incidents in the same vicinity during the early part of July 1972?
Witness indicates that the date of the incident is approximate.  PD