I went out on the patio to sit and enjoy the cool night air. I noticed a bright light in the sky south east from where I was. It was spinning and flashing blue, white and orange red lights. Also moved in all directions, but seemed to maintain a course at the same elevation from ENE to WSW. Over the course of time watching, I noticed that when a plane came by it reacted to it and a beam of light shone from the object to the plane. Perplexed and mystified I yelled for my Mom to come look and she could instantly notice the object in the sky. She was just as dumbfounded as I was. We stared at it till it disappered. We discused it during the time we were watching it and decided that it couldn't be a plane, helicopter or any heavenly body. Over all the object seemed to move slow, but in reality it traveled half the distance of the sky in an hour & 20 min. the strangest thing about the object was the fact that it made so many erratic movements. From up and down to side to side, sometimes slow and sometimes quick. My Mom and I were both amazed and felt somewhat euphoric. Like we were seeing something that you only read about or see on TV, it was right in front of us for an hour and twenty minutes.