We saw a cigar-shaped, craft with pulsating green, red, and yellow lights that defied normal earthly aircraft movements.

My brother and I were looking at the western sky on a warm, night in late July, 1983.  We saw an object that at first looked like a plane.  But, the lights on this object were NOT blinking on and off.  Instead, they were pulsating in different colors of green, red, and yellow.  There were three or four solid round color patterns of green, red, and yellow that seemed to pulsate as they traveled around the craft in a circle while it flew from south to north.  It would move very slowly before speeding up and slowing again performing maneuvers unlike any aircraft I've ever seen.  We (my brother and I)  got into the car to go get completely away from the city lights, and we were able to keep track of it from the car, but lost sight of it about ten or fifteen minutes from the initial sighting. It was as close as an airplane, but made no sound. It definitely did not move like any known earthlike aircraft I have ever seen.
Date is approximate.  PD