Sighting in Sainte-Gemme-la-Plaine, August 26, 2021

On the night of 25 to 26 August 2021, a motorist was driving south on leaving a town in the Vendée when they noticed an unusual light phenomenon. An intense flash, like lightning high in the sky, lit up a large part of the sky ahead, even though the sky was clear and the Moon plainly visible. Immediately afterwards, a stationary blue ball of light appeared near the horizon. It stayed visible for between one and five seconds. The witness judged it slightly smaller than the Moon that evening, with slightly blurred edges.

The driver of the vehicle ahead also saw a flash and a bluish tint, but not the ball. That driver chose not to give an official statement. GEIPAN rated the case's consistency as medium: two witnesses, but only one testimony, and no photo or video.

The investigation looked at lightning and a bolide (a bright meteor). Lightning was ruled out, since no storm activity was detected at the time. The brevity of the sighting fits a bolide, with the flash possibly being a meteoroid entering the atmosphere. Because the phenomenon was seen on the horizon, it was probably over the Gulf of Lion. A FRIPON network sensor in Rome also detected a bolide at a compatible time, but with no trajectory data its direction of travel could not be determined. The blue ball could be due to retinal persistence. The case is classed B: probable observation of a bolide.