Sighting in Bron, November 26, 2013

At around 5:30 pm, a witness noticed several oddly shaped lights in the sky. They were four elongated shapes that seemed to hang motionless in the western sky, where the sun had set. The witness photographed them.

The GEIPAN investigation recognised them as aircraft contrails lit by the sun, which had set shortly before, at about 5 pm, to the south-west at an azimuth of 240°. A Flightradar record shows an aircraft that could have left these trails. In clear weather, contrails can be seen from nearly 80 km away. At that distance the aircraft appears to move very little across the sky, especially when it is heading towards or away from the witness, which explains the impression of stillness. Once the sun sinks too far below the horizon, the trails are no longer lit and become invisible.

GEIPAN classified the case as A: the witness had seen aircraft contrails in the light of the setting sun.