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Annama H chondrite—Mineralogy,physical properties,cosmic ray exposure,and parent body history |
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| Authors: | Tomá? Kohout Jakub Haloda Patricie Halodová Matthias M M Meier Colin Maden Henner Busemann Matthias Laubenstein Marc W Caffee Kees C Welten Jens Hopp Mario Trieloff Ramakant R Mahajan Sekhar Naik Josep M Trigo‐Rodriguez Carles E Moyano‐Cambero Michael I Oshtrakh Alevtina A Maksimova Andrey V Chukin Vladimir A Semionkin Maksim S Karabanalov Israel Felner Evgeniya V Petrova Evgeniia V Brusnitsyna Victor I Grokhovsky Grigoriy A Yakovlev Maria Gritsevich Esko Lyytinen Jarmo Moilanen Nikolai A Kruglikov Aleksey V Ishchenko |
| Institution: | 1. Department of Physics, University of Helsinki, Finland;2. Institute of Geology, The Czech Academy of Sciences, Praha, Czech Republic;3. Finnish Fireball Network, Finland;4. Czech Geological Survey, Prague, Czech Republic;5. Institute of Geochemistry and Petrology, ETH Zurich, Zurich, Switzerland;6. Laboratori Nazionali del Gran Sasso, Istituto Nazionale di Fisica Nucleare, Assergi (AQ), Italy;7. Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana, USA;8. Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana, USA;9. Space Sciences Laboratory, University of California, Berkeley, California, USA;10. Institut für Geowissenschaften, Universit?t Heidelberg, Heidelberg, Germany;11. Klaus‐Tschira‐Labor für Kosmochemie, Heidelberg, Germany;12. Physical Research Laboratory, Ahmedabad, India;13. Institute of Space Sciences (CSIC‐IEEC), Meteorites, Minor Bodies and Planetary Sciences Group, Campus UAB Bellaterra, Cerdanyola del Vallès, Barcelona, Spain;14. Institute of Physics and Technology, Ural Federal University, Ekaterinburg, Russia;15. Institute of Material Science and Metallurgy, Ural Federal University, Ekaterinburg, Russia;16. Racah Institute of Physics, The Hebrew University, Jerusalem, Israel;17. Dorodnicyn Computing Centre, Federal Research Center Computer Science and Control of the Russian Academy of Sciences, Moscow, Russia;18. Institute of Metal Physics, Ural Branch of Russian Academy of Sciences, Russia |
| Abstract: | The fall of the Annama meteorite occurred early morning (local time) on April 19, 2014 on the Kola Peninsula (Russia). Based on mineralogy and physical properties, Annama is a typical H chondrite. It has a high Ar‐Ar age of 4.4 Ga. Its cosmic ray exposure history is atypical as it is not part of the large group of H chondrites with a prominent 7–8 Ma peak in the exposure age histograms. Instead, its exposure age is within uncertainty of a smaller peak at 30 ± 4 Ma. The results from short‐lived radionuclides are compatible with an atmospheric pre‐entry radius of 30–40 cm. However, based on noble gas and cosmogenic radionuclide data, Annama must have been part of a larger body (radius >65 cm) for a large part of its cosmic ray exposure history. The 10Be concentration indicates a recent (3–5 Ma) breakup which may be responsible for the Annama parent body size reduction to 30–35 cm pre‐entry radius. |
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