Sighting in Paris, August 21, 2017

Over two consecutive evenings, between roughly 9 and 11 pm, a witness standing on their 8th-floor balcony noticed lights in the Paris sky. Some seemed to hang motionless while others moved. The witness filmed and photographed them. This was the only testimony received.

The original account suggested that each light stayed in place for a long time. In a phone interview, however, the witness explained that each one lasted no more than one or two minutes. They also said they were looking generally southward, although the questionnaire contained contradictory information and placed the phenomena in the north-east.

Investigators concluded that the lights were the landing lights of aircraft approaching Orly. Planes often arrive from the north, so their lights point toward Paris, at altitudes of 1,000 to 3,000 m and 20 to 60 km from the city. At 400 km/h, an aircraft stays on roughly the same heading toward Paris for 20 km, about 3 minutes, which creates an impression of near-stationarity. At those altitudes the lights would appear only a few degrees above the horizon, consistent with the photos and videos. The witness also recognized the green and red lights of an aircraft on at least one of the lights.

GEIPAN classified the case as A: aircraft observations.