Sighting in Plaisir, April 14, 2013

At around 8 p.m., a witness saw about fifteen very bright points moving across the sky. They were scattered in no particular order, seemed to "flash", and all travelled the same way: starting in the east, they drifted toward the southeast. The witness heard no particular noise during the observation, which lasted about twenty seconds and took place four minutes before sunset.

The investigation found that the sighting could correspond to metallized (Mylar) balloons carried by the wind. At ground level the wind came from the south, but soundings taken at Trappes showed that at altitude it blew from the northwest, which is consistent with the movement described. Filled with helium, such balloons can climb very high and stay aloft for several hours. Their origin is very hard to trace. GEIPAN classified the case as B: probable observation of festive helium balloons.