Sighting in Pont-Saint-Esprit, December 12, 2017

At around 9 p.m., the witness was walking their dog along a small road running beside a railway line. The sky was clear. Their attention was caught by a luminous object passing silently overhead. It was round and matt white, looked as if it were "lit from the inside", and the witness compared it to a ping-pong ball. It appeared above the overhead power lines at about 30° elevation and headed toward an old bridge before changing course. Its apparent size was clearly smaller than the Moon, 23 millimetres on a ruler held at arm's length. It looked largest when it first appeared and shrank as it moved away, at a constant altitude and speed. Its brightness faded gradually with distance, then the object flickered and vanished, at about 15° elevation behind a crane. The witness could not say whether it had switched off or gone behind the houses and trees. The sighting lasted about thirty seconds. The dog did not react. The witness is colour-blind, but the phenomenon was white, so there was no risk of confusing colours. This was the only account collected, and it was supplemented by a phone interview in March 2018.

According to the witness's drawing, the object came from the north-west and moved toward the south-east, consistent with the direction of the bridge. The questionnaire answers, however, mentioned a disappearance to the south-west.

GEIPAN concluded that the witness had probably seen a white LED balloon. The ping-pong-ball colour and the light seeming to come from within fit this kind of balloon, as does the silence. The movement matches a north-west to south-east wind, and the final turn could come from a change in wind direction near the ground. The shrinking size fits a balloon passing close to the witness and then drifting away, and the flickering fits its passing behind trees. Over roughly a hundred metres, the speed is consistent with the wind recorded that evening. Some uncertainty remains, since a winter Tuesday is an unlikely time for a balloon release, but a private party remains possible. The case was therefore classed B.