Sighting in Cugnaux, August 4, 2011

At 22:59 one evening, a witness saw a white point of light cross the sky from south to north. The object's zig-zag movements and changes in brightness caught their attention. They heard no sound during the sighting, and the object eventually passed out of their field of view.

The GEIPAN investigation compared the description with the pass of a satellite, IGS1B, which has a magnitude of 2 (like the pole star) and was following that path at the time given. Its brightness changes during a pass depending on how much sunlight it receives. Seen from the ground, however, a satellite moves in a straight or slightly curved line, which does not match the zig-zags the witness described. These can be explained by the autokinetic illusion, a physiological effect that occurs when the eye follows a point of light against a completely dark background.

The case was classified B: probably a satellite pass, combined with an autokinetic illusion.