Orange ball bouncing up and down, side to side. Changed to green and a few other colors.

November 11, 1979.
Driving in Arizona, saw a bouncing light across the highway. Pulled over off the road, about 30 other cars were also stoped, people were driving by and asking us if we saw it too. Our group was about 6 people, all of us saw something a little different, but it was one light, couldent tell how far. Bouncing up and down side to side. At least 50 other people pulled over saw the light. It went from being orangeish, to greenish, to coming close and being more silver. Another person with us says they thought it was white the hole time. It seemed as if it was following us for 45-50 miles, it would stay parallel to us the hole time, eathier following us, or very far away.
We would welcome reports from the other witnesses.  We believe a "twinkling" star, perhaps Sirius, would be the first possibility to be ruled out.  PD