RICHECOURT (55) 06.11.2020

On 6 November 2020, a witness in his garden in Richecourt (55), between 12:30 and 13:00, watched a translucent, bright white half-moon shape for 1 minute. It was apparently very high in a clear sky, moved very slowly and then “evaporated.” He photographed it. Only 1 account was collected. GEIPAN identifies a high-altitude cloud, cirrus uncinus. It considers this cloud's uncommon appearance likely to have prompted a different explanation from the witness. Supporting features are bright white colour, a half-moon or comma shape dissipating, and slow movement with wind at high altitude; see the investigation report. The strong shine was probably sunlight. The source cites Météo-France to explain that these clouds, at 6–12 km altitude, consist mainly of sparse small ice crystals through which sunlight passes, and that halos or coronas can appear on them. The disappearance was the feature the witness found strange. GEIPAN considers it explainable by light-to-moderate wind generating the comma shape. The evidential substance is good despite a single witness because photographs were taken and could be analysed. GEIPAN classifies the case A: misidentification of a cloud.