An account in Jura, France

On December 19, 1977, around 2 a.m., a motorist driving on the D109 observes a luminous phenomenon in the sky. The unidentified aerospace phenomenon (UAP), shaped like a ball with a flat upper part, emits a whitish glow and seems stationary above a valley. The witness decides to head in that direction and notes that the UAP is moving at a moderate pace toward the West. He will follow the UAP for about thirty minutes without ever catching up to it. No other testimony about this phenomenon was collected by the gendarmerie. This observation case, formerly named Arinthod (39) after the gendarmerie, is one of the cases classified "C" for lack of information and which are now being re-examined (see the document Investigation Notes). This case is fairly consistent (one witness, accompanied by a dog that reacts to the presence of the UAP), and the description of the observed UAP is fairly precise. The sincerity and credibility of the witness have never been questioned. The described phenomenon presents many common characteristics (observation duration, shape, size, color) with a perfectly known astronomical object: the Moon at setting. Moreover, the Moon was indeed present in the area of sky observed, while the witness does not mention it. It is not the witness's visual perception that is in question, but the interpretation the witness makes of their observation through their state of mind (fatigue, night driving). In the current GEIPAN classification, this case of average strangeness is classified "A": observation linked to a misidentification with the gibbous Moon.