Moving in formation in Haute-Garonne, France

On May 17, 2015 at around 11:16 PM, a witness observing the night sky is intrigued by the appearance of a succession of bright points (the witness counted up to 8) which gradually form a large V. The whole thing flies silently at low altitude. One of the points breaks away from the formation and the whole thing disappears. No other testimony will be collected. The witness submitted their testimony to GEIPAN on June 16, 2015, via the GEIPAN questionnaire. A meeting with the witness took place on December 15, 2015 for a cognitive interview and a reconstruction. The strangeness of the case results from the V formation of the lights and their sequence of appearing and going out. The "V" formation is hardly ever found except in two cases: - a patrol of planes or drones flying in formation; - a group of migrating birds. As for the "patrol of planes or drones," it would be surprising at night in an urban environment, and why would the lights of the craft follow such a sequence? The "group of migrating birds" hypothesis, on the other hand, can explain this sequence: - we are a bit outside a migration period, but seagulls and gulls sometimes move at night when their roost is disturbed, for example, and they then fly at low altitude, their white bodies, even barely lit by urban lights, can give a luminous impression (and above all, "white"). It could also be ducks that move at night and frequently form V's; - the entry of the formation into a slightly more lit area could have produced this immediate appearance for each bird (from shadow to sufficient light) and a progressive one for the V. The sequencing of the lights as observed would indicate that the V entered from the left while skirting a more lit area; - everything disappeared at once, which would indicate that the V left the lit area by encountering a shadow front (or less lit) fairly transverse to its movement, while the more lit front causing the appearance was more aligned along the movement; - a bird could very well have broken away from the formation for a brief moment. This is more unusual but is not contradictory, especially since we do not know how long this detachment, which occurred just before the extinction, lasted. This hypothesis was able to be explained with the help of an ornithologist expert. Nevertheless, it was not possible to understand how the lighting configuration of the neighborhood could produce such a sharp and linear contrast at the birds' altitude. That would mean that a fairly small change in lighting can make a white bird appear or disappear in a night sky, or that a particular event that evening (it was a Sunday evening) led to particular lighting. The testimony is consistent. It is precise and was able to be the subject of an on-site reconstruction. Consequently, GEIPAN classifies the case as B: probable observation of birds (migrants in formation). The "bird" phenomenon explanation is recent at GEIPAN; it is possible that certain past unexplained (or poorly explained) observations, including less strange ones (without this particular sequencing of lights here), may in fact fall under this phenomenon.