BAUME-LES-DAMES (25) 17.12.2013

On 17 December 2013 at about 19:15, a witness on a balcony used a new astronomy smartphone app to show his parents the stars. A light absent from the app intrigued him. Through binoculars he saw a round white luminous point that remained stationary for about 15 minutes. He took photographs, numbers 2 and 3 in the photo file, then went inside to warm up. Returning 5 minutes later, he found it gone. No particular sound was heard, and no other account was collected. The stationary white point has all the characteristics of an astronomical observation, but checks were negative. The witness could not identify it with his app. Stellarium (attached document) shows only Fomalhaut in the field, relatively faint at magnitude 1 and too low and too far south. Venus had just set and Jupiter, magnitude −2.7, was northeast. GEIPAN examined other hypotheses: - Aircraft: it remained stationary too long. - Balloon: sunset was at 16:44; at the observation time, the analysis states that only satellites would still be sunlit. - A temporary light on the nearby hill, from a motorcycle, car or an operation: mapped tracks could accommodate a parked vehicle. But the witness gave 45° elevation, far above the hill’s apparent 5° from Baume-les-Dames. - Sky lantern: the photograph’s colour matches lanterns (see “lantern colour space”). Possible release sites along the viewing direction include a recreation centre, a hikers’ hostel and a retirement home. Releases usually occur on weekends or celebrations; this was Tuesday, although near Christmas. Several features fit poorly. The source gives lantern lifetimes of 5–10 minutes, putting this observation at the limit. A point-like binocular appearance is also problematic; the witness should have distinguished a ball or ellipse. Lanterns drift with wind. Besançon records show no wind, but complete immobility remains surprising. A sky lantern is the only hypothesis GEIPAN finds potentially acceptable, and only at the limits of its usual characteristics. It cannot confirm it. The case remains C for lack of precise sky-position data and corroboration.