[meteorite-list] Stubenberg is official

From: Galactic Stone & Ironworks <meteoritemike_at_meteoritecentral.com>
Date: Thu, 12 May 2016 10:29:07 -0400
Message-ID: <CAKBPJW-JOdaQEPs-4p4qGZtr0qZCUcwo=55oB1SqfKPiPM5qTw_at_mail.gmail.com>

Stubenberg is official - http://www.lpi.usra.edu/meteor/metbull.php?code=63192

Stubenberg 48?17.7?N, 13?7.0?E
Bayern, Germany
Confirmed fall: 2016 Mar 6
Classification: Ordinary chondrite (LL6)

History: (Pavel Spurn?, CzAS). A very bright bolide was observed by
thousands of eyewitnesses over Austria, Germany and the Czech Republic
on March 6, 2016, at 21:36:51-56 UT. It was recorded photographically
and photoelectrically by digital all-sky fireball observatories at six
Czech stations of the European Fireball Network. A digital
photographic spectrum of the bolide was also obtained. Based on these
instrumental data, precise results on atmospheric trajectory,
heliocentric orbit, and fragmentation history were quickly determined.
>From this analysis it was evident that this event likely resulted in
multiple stones falling: the impact site was modeled and sent to
German colleagues four days after the fall. All of the meteorites were
found in the predicted location for a given mass.

Physical characteristics: (D. Heinlein). A total mass of 1.473 kg was
recovered within the predicted fall site. The largest fragment has a
mass of 1.320 kg and was found in a 14-cm-deep impact pit. The
remaining 153 g of material consists of several pieces resulting from
five different fragments. The first meteorite, 48 g, was found six
days after the fall: it was broken into many pieces after hitting a
hard surface. The other recovered fragments have masses of 42, 36, 19,
and 8 g.

Petrography: (S. Ebert and A. Bischoff, IfP). Based on the study of
the thin sections, Stubenberg is brecciated. Only highly
recrystallized fragments (type 6) were observed, having only very
rare, indistinct chondrules. Plagioclase (some >100 ?m) and olivine
show undulatory extinction, and the olivines show distinct sets of
planar fractures indicating that the rock is weakly shocked (S3).
Opaque phases include metals (kamacite, taenite), troilite, and
chromite. Other accessory phases include Cl-apatite and merrillite.
Several shock veins cross the meteorite.

Geochemistry: (S. Ebert and A. Bischoff, IfP). The mean composition of
olivine is Fa31.4?0.3 (Fa30.5-32.2, n=54). The low-Ca pyroxenes and
Ca-pyroxenes have mean compositions of Fs25.4?0.3 (Fs24.8-26.1, n= 43)
and Fs11.2Wo41.4 (n=7), respectively. Mean plagioclase composition is
An11.1?0.4Or5.5?1.2 (An10.3-12.1, n= 42). Kamacite has mean Ni and Co
concentrations of 3.9 and 6.1 wt%, respectively (n=8). The taenite
composition is variable, with Ni content varying from 41.9 to 48.2 wt%
(mean: 44.3 wt% Ni, ~1.8 wt% Co, n=38).

Classification: LL chondrite breccia (LL6, S3, W0)

Specimens: Type Specimens: 20.1 g, IfP; the main masses are with the finders.

Received on Thu 12 May 2016 10:29:07 AM PDT

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