Sighting in Lyon, June 28, 2013

At 10:58 pm, a witness saw orange points of light moving in a straight line across the sky above the buildings. Three points first formed a small triangle, followed by three others forming a larger triangle, and finally a single point passed on its own. The witness watched on and off for several minutes, heard no particular noise, and filmed two passes of these orange lights flying in formation. They eventually disappeared behind the urban landscape. Local newspapers ran articles about the sighting.

The witness thought the lights were moving from west to east. However, analysis of the map and the video points instead to a path from north to south, or from north-northwest to south-southeast. This matches the north wind recorded at Bron according to Meteociel, and so is consistent with objects carried by the wind. A release of lanterns at a private party in the La Confluence district had been reported in the press, but the weather data rule out that these were the lanterns the witness saw.

Orange balls drifting with the wind point toward Thai lanterns. A stable triangle formation is common when lanterns are released in threes, and the three stay at equal distances as long as the wind is steady. They may have been launched a few minutes earlier to the northwest of the witness, probably from the Croix-Rousse district, during one of the many private or public parties held in late June. GEIPAN did not try to trace whoever may have released them. The case was classified B: probable sighting of Thai lanterns.