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Chondrules are microscopic, recrystallized melt droplets found in chondritic meteorites. High-resolution isotope analyses of minor elements require large enough element quantities which are obtained by dissolving entire chondrules. This work emphasizes the importance of X-ray computed tomography (XCT) to detect features that can significantly affect the bulk chondrule isotope composition. It thereby expands on other works by looking into chondrules from a wide range of chondrites including CR, CV, CB, CM, L, and EL samples before turning toward complex and time-consuming chemical processing. The features considered are metal and igneous rims, compound chondrules, matrix remnants, and metal contents. In addition to the identification of these features, computed tomography prevents the inclusion of non-chondrule samples (pure matrix or metal) as well as samples where two different chondrule fragments with potentially different isotope compositions are held together by matrix. Matrix surrounding chondrules is also easily detected and the affected chondrules can be omitted or reprocessed. The results strongly encourage to perform XCT before dissolution of chondrules for isotope analysis as a non-invasive method., Meteoritics & Planetary Science, 58 (7), ISSN:1086-9379, ISSN:0026-1114, ISSN:1945-5100

On September 12, 2019 at 12:49:48 (UT) a bolide was observed by hundreds of eye-witnesses from the Netherlands, Germany, Belgium, Denmark and the UK. One day later a small meteorite stone was found by accident in Flensburg. The presence of short-lived cosmogenic radionuclides with half-lives as short as 16 days proves the recent exposure of the found object to cosmic rays in space linking it clearly to the bolide event. An exceptionally short exposure time of ∼5000 years was determined. The 24.5 g stone has a fresh black fusion crust, a low density of, Geochimica et Cosmochimica Acta, 293, ISSN:0016-7037, ISSN:1872-9533

On July 10, 2018 at 21:29 UT extended areas of South-Western Germany were illuminated by a very bright bolide. This fireball was recorded by instruments of the European Fireball Network (EN). The records enabled complex and precise description of this event including the prediction of the impact area. So far six meteorites totaling about 1.23 kg have been found in the predicted location for a given mass during dedicated searches. The first piece of about 12 g was recovered on July 24 close to the village of Renchen (Baden-Württemberg) followed by the largest fragment of 955 g on July 31 about five km north-west of Renchen. Renchen is a moderately-shocked (S4) breccia consisting of abundant highly recrystallized rock fragments as well as impact melt rock clasts. The texture, the large grain size of plagioclase, and the homogeneous compositions of olivine (∼Fa26) and pyroxene (∼Fs22) clearly indicate that Renchen is composed of metamorphosed rock fragments (L5–6). An L-group (and ordinary chondrite) heritage is consistent with the data on the model abundance of metal, the density, the magnetic susceptibility as well as on O-, Ti-, and Cr-isotope characteristics. Renchen does not contain solar wind implanted noble gases and is a fragmental breccia. An unusually large mm-sized merrillite-apatite aggregate shows trace element characteristics like other phosphates from ordinary chondrites. Data on the bulk chemistry, IR-spectroscopy, cosmogenic nuclides, and organic components also indicate similarities to other metamorphosed L chondrites. Noble gas studies reveal that the meteorite has a cosmic ray exposure (CRE) age of 42 Ma and that most of the cosmogenic gases were produced in a meteoroid with a radius of at max. 20 cm based on the radionuclide 26Al and 10–150 cm based on cosmogenic 22Ne/21Ne. K-Ar and U/Th-He gas retention ages are both in the range ∼3.0–3.2 Ga. Both systems do not show evidence for a complete reset 470 Ma ago, and may instead have recorded the same resetting event 3.0 Ga ago., Geochemistry, 79 (4)