QUIEVY (59) 03.09.2024

On 3 September 2024 at 22:15, a witness in the back garden of a home at Quiévy saw an “enormous” white light or round patch in a cloudy sky, apparently above the clouds. It moved rapidly northwest to southeast, stopped for 3 seconds, then continued southeast. The witness estimated its apparent size as about 30 mm on a ruler held at arm's length. The entire observation lasted about 10 seconds. GEIPAN assesses the case as having medium evidential support: there was a single witness and no photograph or video. Under GEIPAN's criteria, evidential support means the quantity of information collected for an account that is considered reliable and objectively established. The described appearance fits a skyward-pointing projector, commonly called a sky-tracer, used for events and celebrations. This is GEIPAN's preferred hypothesis; the source summary calls it a laser light display. The investigation report provides details. The witness mainly found the alternation between movement and stopping unusual. A sky-tracer can sweep rapidly in any direction and remain still for extended periods, so these movements fit its operation. Although the witness considered a projector, they rejected it because the light seemed to come from above the clouds. GEIPAN describes this as a common optical illusion caused by the distance between the ground source and cloud layer, together with cloud density. The powerful beam can create a diffuse patch with indistinct edges that appears to lie beyond the clouds. The source refers to examples on the Méprises du ciel website. The impression is reinforced when the beam itself is invisible. Few suspended particles and excellent horizontal visibility can prevent an observer from seeing the connection between the ground projector and its patch on the clouds. The investigation did not identify a projector operator that evening. A local authority, association or individual might, for example, have tested one briefly before longer use at a celebration the following weekend. GEIPAN classifies the case B: a probable sky-tracer.