Let us begin by reviewing the facts about the visual target. According to the witnesses on the ground, it was a brilliant bluish-white light that appeared on the northeast horizon and remained stationary during most of the period it was observed. At one time it seemed to advance rapidly toward the witnesses, make a wide sweep around Rapid City, which was a few miles away from the observers, and then return to its original position. According to the witnesses in the air, the light did not remain stationary but retreated from the pursuing plane and followed the returning plane, duplicating the plane’s speed and keeping the distance between them constant. The pilots based this interpretation, evidently, on the fact that the light did not vary in size or brilliance and thus seemed to pace the plane. These descriptions all point to the same answer: that the light was a star or a planet. Since it was infinitely distant, the jets could not get any closer to it and at ground levels the image was distorted by peculiar atmospheric conditions. Mars had been absent from the night sky for months, and Mercury, Venus, and Jupiter were then morning stars; therefore the unknown could not have been a planet. However, the bright star Capella was on the northeast horizon at a declination of plus 46 degrees and would have been visible from both Fargo and Rapid City. A check of the Weather Bureau records shows that the night was clear and dark. The sun had set about an hour before the sighting began, and at that time in the evening there was no moonlight because the moon was in its last quarter. Visibility was about thirty-five miles and the wind was from the northeast, about four meters per second. There was a marked temperature inversion--9 degrees--at ground levels. Such an inversion could easily account for the erratic motions reported for the light. There can be little doubt that the visual target was the star Capella. The radar targets also were clearly the result of weather, just as the air-traffic controller had suspected when he first looked at the scope. Conditions were ideal--a calm, clear, warm summer night--for phantom echoes. The first radar target, moving southwest, was probably a return from some ground object. When the jet took to the air, the scope showed a different kind of UFO target, one that echoed the movements of the plane itself--retreating from the pursuer, advancing when the pursuer turned back--and was always farther away from the ground station than the plane itself.