Photographed in Sa�ne-et-Loire, France

The witness, wanting to do a star trail, sets his camera accordingly. The next day, he sees that he has thus captured a luminous object that remained stable, unlike the other stars, which trailed during the 5 minutes of exposure time separating the shots. A luminous point on an astronomy photo with a long exposure most likely reveals a brief luminous event, rather than a fixed phenomenon during the 5 minutes of the exposure. This luminous point turns out, moreover, to be a small streak, revealing a partial movement during the 5 minutes of exposure. The favored hypothesis is the reflection of the sun on a satellite: the attached "Calsky" report indicates that the satellites NOSS 3-3A and 3C were passing at that moment in the camera's field of view, culminating at 27° above the horizon (it would seem that the point on the photo is a little higher). It seems that the satellite NOSS 3-3C (28541) see: Satflare NOSS3-3C may have a more powerful and more variable brightness than NOSS3-3A (28537) see: Satflare NOSS3-3A. The small black streak observed under the white streak when zooming in on the photo is probably a side effect of the jpeg compression ("rebound" of the white line: it is indeed a shame that the photos were not taken in "raw". On the attached photo of the Pleiades, greatly enlarged, one sees that each star image is surrounded by a black line: it is the same compression artifact. GEIPAN classifies this case "B": probable photograph of a satellite flare. (There remains an uncertainty about the satellite from which the flare originated).