Lights in shape of "radio tower" flew north

Three of us, former Marine NCO's, were varmint hunting in the grasslands north of Douglas, Wyoming. We had gone into town to eat and upon our return to camp we noticed a radio tower (rather the lights) east of the road, two of us were quite familiar with the area and unaware of the tower. We stopped and commented on the tower which was just over a hill from us. As we drove on a taller hill occluded the tower. When we rounded the hill we looked back to try and triangulate the position of the tower. We found the tower had moved! It was still due east of us and much too close to be parallax. It was a warm evening, the windows were open, there was no sound. I shut off the engine, the "tower" began to move, it moved due north at an increasing speed. One of my friends aimed his varmint rifle at the "tower" and watched it until it disappeared from view without any course deviation, this was perhaps a minute after it was lost to naked eye view. There was never a change in color or configuration while I watched. The lights were in the shape of a pyramidal type TV or radio tower all lights were white in color, and about as bright as the marker lights on such a tower, much brighter than any stars. My friend stated that through the 20x rifle scope he could see no features or shape only the lights. He stated there was nothing between the lights, he could see the stars through the formation. The speed of the objects could not be estimated, but appeared to move at a constant acceleration, probably at about mach 2-3 before dwindling from sight, alternatively the lights dimmed and the formation closed at a constant rate. Discerning the difference would require a range finder or triangulation neither of which was available.