CHALLES-LES-EAUX (73) 11.10.2017 T1

Around 14:30 on 11 October 2017, a witness reclining on a deckchair in Challes-les-Eaux (73) was looking south into a clear sky when a roughly round white object, described as the size of a handball, passed rapidly eastward. After about 1 minute he suddenly saw it move backwards. He went to get his phone for a photograph. On returning he had trouble finding the UAP, but eventually photographed it and saw a bright white patch on his screen. Still intrigued, he searched the sky with his phone again and found a smaller object, which then disappeared from view. Sitting back down, he noticed floating filaments in the sky. His daughter, who was present, also saw the threads. He took several photographs and later found some threads caught on his cherry tree. Only 1 account was collected. GEIPAN assessed the account as well supported and precise. The witness supplied all the information needed for a sound analysis, with photographs providing valuable additional evidence. Research and analysis identified 2 phenomena; see the investigation report. First, 2 aircraft crossed at the same time and at the same apparent position, creating the illusion that a single object had reversed direction. Second, the photographed filaments were gossamer, commonly called “fils de la Vierge” in French: silk threads carrying tiny young spiders on the wind, a form of travel known as ballooning. GEIPAN classified both related cases A: CHALLES-LES-EAUX (73), 11 October 2017 T1, misidentification of airliners; and CHALLES-LES-EAUX (73), 11 October 2017 T2, observation of ballooning.