Sighting in Blois, December 28, 2017

At about five in the morning, under a clear sky, a witness watched two points of light move from north to south for roughly thirty seconds. They heard no particular sound. The two points eventually vanished behind the horizon. Only one account was collected.

The investigation found that a pair of NOSS satellites, which orbit as a duo, was nearing the end of its visibility pass on roughly the same path as the one described, at the approximate time the witness gave. According to Calsky data, their magnitude (about 3) is faint, lower than that of Spica, the star the witness compared them with, but still within the range visible to the naked eye. The witness's estimate of the duration, between 30 seconds and 1 minute, is too imprecise to confirm a satellite pass; since they had no watch, they may have underestimated it.

This imprecision means the satellite hypothesis cannot be stated with certainty, but it is highly probable given the distinctive nature of a satellite pair. GEIPAN classified the case as B: probable observation of two satellites following one another along the same trajectory.