Sighting in Triplet de Satellites — National, August 11, 2018

A witness followed three grouped points of light moving in a straight line across a clear night sky at about 23:10 local time. Two other reports describing the same scene, around 23:00 the same night, reached the GEIPAN, making three independent reports from three different départements. In those two reports, the first point, at the front, was less visible than the others. The investigation examined the first report in detail. Conditions were ideal: mild temperatures, a very clear sky, no moon, and a night when more people than usual were watching the sky (the "shooting stars night").

The GEIPAN identified a triplet of Chinese surveillance satellites, Yaogan-31 A, B and C, launched a few months earlier and then in a temporary configuration that made them visible to the naked eye. Their appearance matched that of satellites: brightness, colour, point-like look and straight path, as the witness had noted. The satellites were indeed in the sky at that moment. A satellite specialist, whose own report was very detailed, gave the same starting and ending elevations as the witness, and a reconstruction in Stellarium confirmed them: the triplet was then at its culmination, at an elevation of about 75°. The witness had probably greatly overestimated the angular movement and slightly underestimated the duration. Their final direction was wrong, probably because trees and houses hid much of the horizon, the observation was brief, and the objects were high, close to the zenith. What struck the witness was seeing three objects travel together with no stars visible. Such movement in threes is possible for NOSS-type surveillance satellites, American and now Chinese, and the triplet was probably crossing an area of sky without stars bright enough to be seen. The case was classified A.