Sighting in Sceaux, June 4, 2023

From the window of their third-floor apartment, the witness saw a dark, round object cross the sky at 9:29 pm. It was fairly fast, steady and not very high. It moved in a straight line and vanished behind a building after about a minute. The witness made out what looked like "flames" on it, which they thought could be reflections on a metal frame. They filmed the scene with their mobile phone.

The case was considered to be of good consistency: there was only one witness, but the video could be used. Its appearance on screen quickly suggested a mylar balloon. Using easily identifiable visual landmarks, analysis of the video made it possible to pin down the path: it ran roughly north to south, not north-west to east as the witness had reported. That direction matches the wind at that hour, which blew at 20°, from the NNE toward the SSW. The "flames" are explained by the rays of the setting sun reflecting off the mylar of a balloon that was spinning on itself as the wind carried it. Its round shape, flattened and hollowed, accounts for the uneven way the flashes appeared.

The witness therefore most probably saw a mylar balloon carried by the wind, about 100 m away. GEIPAN classified the case as A.