The Braunschweig meteorite - a recent L6 chondrite fall in Germany
Résumé
On April 23rd 2013 at 2:07 a.m., a 1.3 kg meteorite fell in the Braunschweig suburb Melverode (52 degrees 13' 32.19'' N. 10 degrees 31' 11.60'' E). Its estimated velocity was 250 km/h and it formed an impact pit in the concrete fall site with a diameter of 7 cm and a depth of 3 cm. Radial dust striae are present around the impact pit. As a result of the impact, the meteorite disintegrated into several hundred fragments with masses up to 214g. The meteorite is a typical L6 chondrite, moderately shocked (S4) - but with a remarkably high porosity (up to 20 vol%). The meteorite was ejected from its parent body as an object with a radius of about 10-15 cm (15-50 kg). The U,Th-He gas retention age of similar to 550 Ma overlaps with the main impact event on the L-chondrite parent body similar to 470 Ma ago that is recorded by many shocked L chondrites. The preferred cosmic-ray exposure age derived from production of radionuclides and noble gas isotopes is (6.0 +/- 1.3) Ma. (C) 2016 Elsevier GmbH. All rights reserved.