Sighting in Nantes, November 22, 2020

On a Sunday evening, shortly after sunset at around 6 p.m., the witness noticed a red-orange light about 20° above the eastern horizon. It seemed to move slowly at first, then faster as it came closer. More lights then appeared, about ten in all, roughly circular and bright, following one another at regular intervals. They headed south / south-west at a fairly low altitude, beneath the clouds, and left the witness's field of view. One of them veered west at the last moment. The witness had time to take 8 photos, which were sent to the GEIPAN. No other witness account was collected.

What struck the witness most was the sudden turn to the west, with strong acceleration. The GEIPAN considers the case solid: the witness's details are very precise and the photos add real value. The witness had considered many possible explanations, but not lanterns.

Yet the red-orange color, the roughly circular shape, the straight path, the even spacing and the fact that it was a weekend evening all point to Thai lanterns. The colors and shapes seen in the photos are typical of such lanterns, and the IPACO tool gives a chromaticity for one of the lights that matches. The Bouguenais weather station, 11 km away, recorded a light wind of about 4 km/h from the south to south-south-west between 5 and 7 p.m., consistent with the direction of travel, and lanterns are only released in light wind. The sharp turn most likely comes from an optical illusion: when a lantern goes out, it seems to speed away, and depending on the relative positions this can look like a change of direction. The prefecture had received no release request for that date, but such rules are seldom followed at private parties, so tracing the origin of the release is nearly impossible. This set of converging clues points to a probable misidentification of Thai lanterns; since the origin of the release could not be established, the GEIPAN classified the case B.