An account in Tarn, France

On April 13, 2015, from 10:10 PM to 11:30 PM, a witness observed with the naked eye and then with binoculars two colored luminous phenomena in the sky. An observation lasting more than an hour of luminous objects in the sky, multicolored, moving slowly, according to the Earth's rotation (15°/hour) is typical of the observation of celestial bodies. In this case, the directions indicated by the witness are not very precise but seem to point to the stars Procyon and Capella, which are however less bright than Sirius, or especially than the planets Venus and Jupiter (see the sky charts made with the software "Stellarium" for Albi at 10:10 PM and 11:10 PM). The strange part of the observation lies in the description of changing colors, and of the shape of a sea urchin test (shell). The Meteociel data for the day indicates high temperatures for the season (27°): see the weather. These significant temperature differences induce turbulence in the atmosphere, causing strong twinkling, particularly visible with binoculars. It is these somewhat unusual atmospheric conditions that gave this appearance to the observed celestial bodies. This type of twinkling also occurs in strong wind, especially if it is warm. It should also be noted that the witness observes with hiking binoculars (10x25) with a high magnification of 10, but a small aperture of 25mm, poorly suited for astronomical observation (for that, one prefers a lower magnification of 7 or 8, and a larger aperture of 50 mm). These binoculars can induce shape and color aberrations in these particular conditions; the high magnification makes a stable view very difficult, when held by hand. GEIPAN classifies this case as B: observation of celestial bodies. A more precise testimony, positioning the celestial bodies relative to each other, would have allowed a more exact identification of the celestial bodies in question.