Meteoritical Bulletin: Entry for Braunschweig

Writeup from MB 102:

Braunschweig 52°13.548’N, 10°31.193’E

Niedersachsen, Germany

Fell: 2013 Apr 23, 02:05 a.m.

Classification: Ordinary chondrite (L6)

History: (R. Bartoschewitz, Bart) Erhard Seemann found a rock impacted into the concrete pavement in his yard 3 m from his front door on the morning of April 23, 2013. He documented his observation and collected the main fragments (~700 g) of the nearly complete fragmented stone. A neighbor heard a strong hum followed by a loud crash that night at about 2:10 a.m. In the morning he found several small rock fragments (~25 g) in his gateway. In Ahlum village, Julian Mascow was surprised by a bright flare coming from the SE, ending in a short tracer just over his head. About 90 s later he was startled by an explosion and ensuing rattling sound around him. Mark Vornhusen’s web camera documented the fireball from Vechta. When Rainer Bartoschewitz documented the meteorite impact, he discovered many small fragments (~500 g) within 18 m of the others.

Physical characteristics: (R. Bartoschewitz, Bart) One meteorite of about 1.3 kg broken into hundreds of small fragments after impacting the concrete pavement. The biggest fragment, 214 g, stuck in the concrete making a 7-cm diameter by 3-cm deep depression. Other fragments were <30 g. The gray-white meteorite material is covered by a 0.4-mm thick dull black fusion crust with abundant 50 μm cracks. Magnetic susceptibility log χ = 4.75.

Petrography: (R. Bartoschewitz, Bart) Recrystallized matrix of olivine, pyroxene (0.02-0.5 mm) and secondary feldspar hosting poorly developed and deformed, dominantly barred olivine chondrules (0.5 to 15 mm, av. 1.5 mm), metal, troilite and chromite. Dark metal-troilite veins (50 µm) cross the meteorite.

Geochemistry: (R. Bartoschewitz, Bart, P. Appel and B. Mader, Kiel) olivine Fa_24.3-26.0(mean Fa_25.2±0.40, n=33); Ca-poor pyroxene Fs_20.8-21.7Wo_1.0-1.8(mean Fs_21.3±0.24Wo_1.6±0.20, n=12); Ca-rich pyroxene Fs_8.1-8.8Wo_44.4-45.2(mean Fs_8.4±0.40Wo_44.7±0.35, n=4); feldspar An_11-18Or_4-10, chromite Cr/(Cr+Al)=88.3, Fe/(Fe+Mg)=79.8. Kamacite Ni=4.7-6.2, Co=1.0; taenite Ni=20-34, Co=0.3-0.7 (all in wt.%)