hovering 25' up, middle section rotating clockwise and containing red, yellow and (green?) lighted sections, shot away fast, no sound.

1972, July 4th fireworks had just ended and there were a lot of cars slowly driving away from the event, "stuck in traffic".  I was a young girl, with my sister, mother & father in one of these cars - a silver metallic saucer hovered - no sound- about 25' in the air over the cars about 5 or 6 cars ahead of us, we had a very clear view.  There were three horizontal parts - the middle horizontal part of the craft rotated slowly, with red, yellow, and other colored rectangular lighted sections with rounded corners all about the same size in this rotating section, which rotated clockwise from our perspective.  Top and bottom parts were not rotating.  After a few minutes, the craft shot up and away at a high speed at about a 45 degree angle, again no sound or vibrations. 
Witness elects to remain totally anonymous; provides no contact information.  PD