![]() ![]() ![]() They are classified as L6 ordinary chondrites (Bischoff et al. Three meteorites with a total weight of 3.6kg (until April 2010) were found in a high mountain area near the town of Jesenice. The Jesenice orbit is markedly different from the Příbram and Neuschwanstein orbital meteorite pair, which fell on similar dates (April 7, 1959, and April 6, 2002, respectively). Both the atmospheric behavior and the heliocentric orbit proved to be quite normal in comparison with other observed meteorite falls. Using a detailed fireball light curve, we modeled the atmospheric fragmentation of the meteoroid. From all these records, we reconstructed the fireball's atmospheric trajectory, basic geophysical data, the possible impact area, and the original heliocentric orbit of the meteoroid. In addition to these optical recordings, the sonic booms produced by the Jesenice fireball were detected at 16 seismic stations located within 150km of the trajectory. Simultaneously, a part of the luminous trajectory was also captured by two all-sky CCD systems and one video camera of the Slovenian meteor network. ![]() The fireball designated EN090409 was recorded photographically and photoelectrically by two southern stations of the Czech part of the European Fireball Network (EN). We report an analysis of instrumental observations of a very bright fireball which terminated with a meteorite fall near the town of Jesenice in Slovenia on April 9, 2009, at 0h59m46sUT. The forthcoming return of cometary samples by the Stardust mission will provide a unique opportunity to corroborate (or contradict) our hypothesis. If CI1 chondrites originate from comets, it implies that comets are much more processed than previously thought and should contain secondary minerals. A cometary origin of the Orgueil meteorite does not contradict cosmochemistry data on CI1 chondrites. This is at odds with other meteorites that have an asteroidal origin, but it is compatible with 140 years of data-gathering that has established the very special nature of Orgueil compared to other meteorites. These results suggest that Orgueil has an orbit similar to that of Jupiter-family comets (JFCs), although an Halley-type comet cannot be excluded. From the calculated atmospheric path and the fireball duration, which was reported by seven witnesses, we have estimated the pre-atmospheric velocity to be larger than 17.8 km/sec, which corresponds to an aphelion distance Q larger than 5.2 AU, the semi-major axis of Jupiter orbit. The aphelion distance (Q) depends critically on the pre-atmospheric velocity. In particular, the perihelion lies inside the Earth's orbit (q ˜0.87 AU), as is expected for an Earth-crossing meteorite, and the orbital plane is close to the ecliptic (i ˜0°). Five out of six orbital parameters for the Orgueil orbit are well constrained. These characteristics are broadly similar to that of other meteorites for which the trajectory is known. The calculated luminous path was ˜150 km with an entry angle of 20°. The atmosphere entry point was ˜70 km high and the meteoroid terminal point was ˜20 km high. Despite the intrinsic uncertainty of visual observations, we were able to calculate a reasonably precise atmospheric trajectory and a moderately precise orbit for the Orgueil meteoroid. Abstract- Using visual observations that were reported 140 years ago in the Comptes Rendus de l'Académie des Sciences de Paris, we have determined the atmospheric trajectory and the orbit of the Orgueil meteorite, which fell May 14, 1864, near Montauban, France. ![]()
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