NANTES (44) 22.11.2020

On Sunday, November 22, 2020, the witness observed a red orange light at 20° to the east at about 6 pm (not long after sunset). The speed initially seemed low, then higher as it drew closer to the witness (the French wording is ambiguous about the approach). Other UAPs appeared, generally bright, roughly circular, about ten, following at regular distances. They headed south/southwest at a rather low altitude (under the clouds) and came out of his field of vision. One of them veered west at the last moment. The witness had time to take 8 photographs (see the photo file sent by the witness to GEIPAN with an image reduction for mailing). No other witness account of this phenomenon was collected. The strangeness perceived by the witness is mainly due to the fact that one of the UAPs suddenly veered westward with a strong acceleration. The evidential quality of the record is good, the witness's data is very accurate and the photographs strengthen the account. The witness considered many possible misidentifications, but did not mention the lantern hypothesis. However, the colour "orange red", the form "generally circular", the straight displacement with UAP spaced at equal distance, the fact that it is a weekend evening, point toward sky lanterns. The observation is indeed compatible with sky lanterns: - aspect: the orange red colour and the shapes observed on the photos are quite typical of lanterns, - trajectory: the UAPs follow, direction SSW, which is typical of lanterns carried by the same airflow. The Bouguenais weather station located 11 km from the observation site reports an average wind of 4km/h, oriented S at 6pm and SSW at 5pm, SSW at 7pm (see weather document). The indicated direction is compatible with the direction of displacement of the UAPs. The average winds are low: 4km/h, and the lantern releases are only in low winds, - Sunday evening: weekend evening (more conducive to lantern release), - photographic analysis: according to the IPACO tool, the average UAP chromaticity shown in photograph DSC06315cadr.jpg is quite consistent with that of a sky lantern (see IPACO document). The strangeness perceived by the witness is mainly due to the observation of lateral acceleration at a dizzying speed, of one of the UAPs that veered westward. This perception can be due to the following optical illusion: when the lantern is extinguished, the observer has the impression that the lantern is receding extremely quickly, and depending on the respective observer/lantern positions, this may lead to this impression of a change of direction, with the shift to the west representing recession away from the line of UAPs continuing southward. The prefecture of Loire Atlantique had received no application for permission to release lanterns on that date. It also mentioned that the commune of Nantes formally prohibited any release of balloons or Chinese lanterns over its territory. Applications to release balloons or Chinese lanterns on neighbouring municipalities require favorable opinions from the Pays de la Loire delegation of the western Civil Aviation Safety Directorate. Unfortunately, this rule is not followed for the release of lanterns during private celebrations and it is therefore very difficult to trace the origin of a release. GEIPAN considers the closely converging evidence indicative of sky lanterns. The impossibility of defining the origin of the release implies a classification B by the GEIPAN.