تقرير
Exogenic Basalt on Asteroid (101955) Bennu
| العنوان: | Exogenic Basalt on Asteroid (101955) Bennu |
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| المؤلفون: | D N DellaGiustina, H H Kaplan, A A Simon, W F Bottke, C Avdellidou, M Delbo, R-L Ballouz, D R Golish, K J Walsh, M Popescu, H Campins, M A Barucci, G Poggiali, R T Daly, L Le Corre, V E Hamilton, N Porter, E R Jawin, T J McCoy, H C Connolly Jr, J L Rizos Garcia, E Tatsumi, J de Leon, J Licandro, S Fornasier, M G Daly, M M Al Asad, L Philpott, J Seabrook, O S Barnouin, B E Clark, M C Nolan, E S Howell, R P Binzel, B Rizk, D C Reuter, D S Lauretta |
| المصدر: | Nature Astronomy. 5(1) |
| بيانات النشر: | United States: NASA Center for Aerospace Information (CASI), 2020. |
| سنة النشر: | 2020 |
| مصطلحات موضوعية: | Lunar And Planetary Science And Exploration |
| الوصف: | When rubble-pile asteroid 2008 TC3 impacted Earth on October 7, 2008, the recovered rock fragments indicated that such asteroids can contain exogenic material. However, spacecraft missions to date have only observed exogenous contamination on large, monolithic asteroids that are impervious to collisional disruption. Here we report the presence of meter-scale exogenic boulders on the surface of near-Earth asteroid (101955) Bennu - the 0.5-km, rubble-pile target of the OSIRIS-REx mission which has been spectroscopically linked to the CM carbonaceous chondrite meteorites. Hyperspectral data indicate that the exogenic boulders have the same distinctive pyroxene composition as the howardite-eucrite-diogenite (HED) meteorites that come from (4) Vesta, a 525-km diameter asteroid that has undergone differentiation and extensive igneous processing. Delivery scenarios include the infall of Vesta fragments directly onto Bennu or indirectly onto Bennu’s parent body, where the latter’s disruption created Bennu from a mixture of endogenous and exogenic debris. Our findings demonstrate that rubble-pile asteroids can preserve evidence of inter-asteroid mixing that took place at macroscopic scales well after planetesimal formation ended. Accordingly, the presence of HED-like material on the surface of Bennu provides previously unrecognized constraints on the collisional and dynamical evolution of the inner main belt. |
| نوع الوثيقة: | Report |
| اللغة: | English |
| تدمد: | 2397-3366 |
| DOI: | 10.1038/s41550-020-1195-z |
| URL الوصول: | https://ntrs.nasa.gov/citations/20205007912 |
| ملاحظات: | 828928.07.02.03.02 NNM10AA11C ANR-18-CE31-0014 ANR-15-IDEX-01 ISA 2017-37-H.0 |
| رقم الأكسشن: | edsnas.20205007912 |
| قاعدة البيانات: | NASA Technical Reports |
Find this article in full text from Springer Verlag. 
Full Text Finder | تدمد: | 23973366 |
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| DOI: | 10.1038/s41550-020-1195-z |