Sighting in Lyon, June 6, 2015

Shortly after midnight, two witnesses noticed an orange-colored mass in the sky above the city. Inside it stood out a geometric shape, also orange but lighter. The phenomenon then moved away very quickly in a straight line, and no sound was heard. The witnesses themselves thought of a cloud, though they raised a few objections: the color, the geometric shape at the end, and the fast movement.

The investigation addressed each of these. A low cloud over a city acts as a screen for urban lighting: it can reflect the orange of street lamps, especially near a stadium or a large, brightly lit road junction, or reproduce the beams of searchlights aimed at the sky. That night the sky was overcast at Lyon-Bron and the wind blew from the south to south-west, matching the direction in which the phenomenon moved. An Ethnotek event was taking place in the Gerland park, in a direction close to that of the phenomenon, and its lighting effects may have lit the sky in an unusual way. Clouds often change shape quickly, and some shapes, geometric ones in particular, are more striking than others. Only one witness mentioned the fast movement, without presenting it as a specific objection, and nothing objective suggested a speed inconsistent with a cloud carried by the wind, which is often stronger at altitude.

The GEIPAN concluded that the witnesses had probably seen a cloud and classified the case as B.