Sighting in Taverny, January 4, 2010

At about 7:45 p.m., a witness out for a walk noticed a large, dark, triangular shape moving from east to west. At each end was a dim, yellow-orange circle of light. The object moved at a constant speed, and the witness heard no particular noise during the 10 to 15 seconds of the sighting. No other witness was found.

The investigation confirmed and clarified the content of the account and lent credibility to the witness's statement. The sighting did not resemble the usual misidentifications and did not match an airliner passing by, especially since the witness was very used to watching aircraft. A model aircraft or drone about 2.5 m across, flying at 150 m altitude at roughly 35 to 150 km/h beneath the radar cone of Roissy-CDG air traffic control, would have been consistent with the description. However, it seemed very unlikely that such a craft would fly over an urban area, at night, on a winter evening, so this hypothesis was not adopted for lack of other convincing evidence. The case rested on a single witness, with no photo or video, and despite the quality of the testimony its consistency remained moderate. GEIPAN classified it D1, an unexplained phenomenon.