Sighting in Montmorency, December 18, 2020

At nightfall, a witness and their daughter noticed a very bright group of three points in the sky, forming a nearly equilateral triangle. The points changed in brightness and the whole group seemed to move. After a few seconds, in less than a minute, all three went out almost at the same time. The witness compared the sight to three ISS arranged in a triangle.

GEIPAN rated the case's consistency as average: there was a single, well-detailed testimony, but no photo or video. The investigation concluded that the witness had seen a triplet of Chinese satellites, Yaogan-31 A, B and C, in a temporary configuration in which each one reflected sunlight toward the witness, making them visible to the naked eye. Several points support this: three satellites moving together, which is typical of this kind of satellite; an appearance consistent with satellites (brightness, color, point-like look, straight path), which the witness had noted too; their confirmed presence in the sky at that moment, according to data from the CNES Operational Centre for Space Surveillance; elevations given by the witness matching the triplet's trajectory to within 1.5 minutes; a duration in line with the visibility of such flashes, as in other cases GEIPAN has studied; and a correctly estimated viewing direction and angular spacing between the three components (5°). The case was classified "A".