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"The fireball started its almost 92 km long luminous trajectory at an altitude of 85.6 km about 15 km NE from Innsbruck, Austria (longitude 11.564 deg E, latitude 47.304 deg N). Maximum brightness of about -18 absolute magnitude was reached in a bright flare at a height of 21 km near Garmisch-Partenkirchen, Germany (longitude 10.91 deg E, latitude 47.51 deg N). The fireball terminated at an altitude of only 15.8 km about 20 km W from Ga-Pa (longitude 10.85 deg E, latitude 47.53 deg N). Such deep penetration of a fireball is very scarce and this fireball belongs to the deepest ever-photographed fireballs in the history. It also implicates, that some part of the initial mass survived the ablation processes in the atmosphere and landed on the ground as meteorites. The slope of the atmospheric trajectory to the Earth's surface was 49.5 degrees. The fireball entered the atmosphere with the velocity of 20.9 km/s and during its flight substantially decelerated to the final value of only 4 km/s, when ablation process was stopped. According to the dynamic behavior in the atmosphere this fireball belongs to the fireball type I, which is usually identified with stony material, mostly ordinary chondrites. The initial dynamic mass of the entering meteoroid was about 500 kg and most of this mass was ablated and only about 30 kg of total mass could land on the ground in several fragments. The impact area is relatively large, it is at least several kilometers long and about 1km wide. The main fragments will lie eastwards from Schwangau, Germany. Smaller fragments could be found also around the Austria-Germany border westwards from Ga-Pa. The whole area is located in high mountains (the Alps), which is unfortunately very unfavorable for any systematic search. "From the exact time of the fireball occurrence, its initial velocity, and the position of the radiant, we computed the heliocentric orbit. We found that the body, before its collision with Earth, orbited the Sun on an elliptic orbit defined by the following orbital elements: semimajor axis 2.4 AU, eccentricity 0.67, perihelion distance 0.79 AU, argument of perihelion 241.4 degrees, longitude of ascending node 16.8 degrees and inclination 11.4 degrees. Such kind of heliocentric orbit is quite usual for fireballs which penetrate very deep into the Earth's atmosphere and which can produce meteorites. The aphelion of these orbits lies in the main belt of Asteroids and therefore the asteroidal origin of these bodies is inferred. However, the heliocentric orbit of this fireball has one very significant exceptionality: we found that this orbit is the same as the orbit of the first photographed meteorite fall in the history - the Pribram meteorite fall on April 7, 1959. Both orbits are so close that there is no doubt that both bodies have the same origin. It is very important evidence for the existence of asteroidal streams and meteorite streams as suggested earlier by Halliday and others. From observations of both bolides we know that both bodies were far from each other in the orbit (probably about half of the period) when the Pribram collided with the Earth. It implies that many such bodies have to be on this orbit, because it is fantastic chance to photograph two meteorite falls from the same orbit on practically the same territory within only 43 years! It also substantiates why it is important to operate such long term observing program as the European Fireball Network is. "Finally, from the perfect similarity of both heliocentric orbits we can predicate, that both bodies had also the same composition and therefore we can expect that meteorites produced by the April 6 fireball are H5 ordinary chondrites." --Pavel Spurny --Astronomical Institute of the Academy of Sciences --Ondrejov Observatory --The Czech Republic --e-mail: [EMAIL PROTECTED] If this meteorite should prove to be an H5, and paired
to Pribram, this will
be a very huge discovery indeed! I'm sure we are
all very anxious to hear
about classification
results!
Congratulations again, and good hunting for additional
specimens! --Rob
-----Original Message-----
From: Thomas Kurtz [mailto:[EMAIL PROTECTED]] Sent: Tuesday, July 30, 2002 7:50 AM To: Meteoriten-Mailingliste Subject: [meteorite-list] NEW ! ! ! First found of the Neuschwanstein" Meteorite Hello list,
The first piece is 1750g big ! It was found on
14.7.2002 , 6 km SO from "Neuschwanstein"-castle !
Very nice individual and very fresh !
Look this Link for picture :
http://www.wetteragentur.de/modules.php?op=modload&name=News&file=article&sid=10556&mode=&order=0 With best wishes, Thomas Kurtz.
Web Site : http://www.stud.fh-hannover.de/~kurtzt
Mobile-phone : +49 (0)
160-98117639 |
