دورية أكاديمية
Asteroid (16) Psyche’s primordial shape: A possible Jacobi ellipsoid
| العنوان: | Asteroid (16) Psyche’s primordial shape: A possible Jacobi ellipsoid |
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| المؤلفون: | Ferrais, M., Vernazza, P., Jorda, L., Rambaux, N., Hanuš, J., Carry, B., Marchis, F., Marsset, M., Viikinkoski, M., Brož, M., Fetick, R., Drouard, A., Fusco, T., Birlan, M., Podlewska-Gaca, E., Jehin, E., Bartczak, P., Berthier, J., Castillo-Rogez, J., Cipriani, F., Colas, F., Dudziński, G., Dumas, C., Ďurech, J., Kaasalainen, M., Kryszczynska, A., Lamy, P., Le Coroller, H., Marciniak, A., Michalowski, T., Michel, P., Santana-Ros, T., Tanga, P., Vachier, F., Vigan, Arthur, Witasse, O., Yang, Bin |
| المساهمون: | Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute of Charles University, Univerzita Karlova Praha, Česká republika = Charles University Prague, Czech Republic (UK), European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Astrophysics Research Centre Belfast (ARC), Queen's University Belfast (QUB), Tampere University of Technology Tampere (TUT), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Uniwersytet im. Adama Mickiewicza w Poznaniu = Adam Mickiewicz University in Poznań (UAM), European Southern Observatory (ESO), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), European Space Research and Technology Centre (ESTEC), Astronomical Observatory Poznan, Laboratoire associé de Reconnaissance cellulaire et amélioration des plantes, Institut National de la Recherche Agronomique (INRA), Department of Mathematics Tampere, Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UniCA)-Université Côte d'Azur (UniCA)-Centre National de la Recherche Scientifique (CNRS), Northeastern University Shenyang |
| المصدر: | ISSN: 0004-6361. |
| بيانات النشر: | HAL CCSD EDP Sciences |
| سنة النشر: | 2020 |
| المجموعة: | Archive de l'Observatoire de Paris (HAL) |
| مصطلحات موضوعية: | minor planets, asteroids: general, asteroids: individual: (16) Psyche, methods: observational, techniques: high angular resolution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
| الوصف: | International audience ; Context. Asteroid (16) Psyche is the largest M-type asteroid in the main belt and the target of the NASA Psyche mission. It is also the only asteroid of this size (D > 200 km) known to be metal rich. Although various hypotheses have been proposed to explain the rather unique physical properties of this asteroid, a perfect understanding of its formation and bulk composition is still missing.Aims. We aim to refine the shape and bulk density of (16) Psyche and to perform a thorough analysis of its shape to better constrain possible formation scenarios and the structure of its interior.Methods. We obtained disk-resolved VLT/SPHERE/ZIMPOL images acquired within our ESO large program (ID 199.C-0074), which complement similar data obtained in 2018. Both data sets offer a complete coverage of Psyche’s surface. These images were used to reconstruct the three-dimensional (3D) shape of Psyche with two independent shape modeling algorithms (MPCD and ADAM). A shape analysis was subsequently performed, including a comparison with equilibrium figures and the identification of mass deficit regions.Results. Our 3D shape along with existing mass estimates imply a density of 4.20 ± 0.60 g cm−3, which is so far the highest for a solar system object following the four telluric planets. Furthermore, the shape of Psyche presents small deviations from an ellipsoid, that is, prominently three large depressions along its equator. The flatness and density of Psyche are compatible with a formation at hydrostatic equilibrium as a Jacobi ellipsoid with a shorter rotation period of ∼3h. Later impacts may have slowed down Psyche’s rotation, which is currently ∼4.2 h, while also creating the imaged depressions.Conclusions. Our results open the possibility that Psyche acquired its primordial shape either after a giant impact while its interior was already frozen or while its interior was still molten owing to the decay of the short-lived radionuclide 26Al. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| العلاقة: | hal-02898978; https://hal.science/hal-02898978Test; https://hal.science/hal-02898978/documentTest; https://hal.science/hal-02898978/file/aa38100-20.pdfTest; BIBCODE: 2020A&A.638L.15F |
| DOI: | 10.1051/0004-6361/202038100 |
| الإتاحة: | https://doi.org/10.1051/0004-6361/202038100Test https://hal.science/hal-02898978Test https://hal.science/hal-02898978/documentTest https://hal.science/hal-02898978/file/aa38100-20.pdfTest |
| حقوق: | info:eu-repo/semantics/OpenAccess |
| رقم الانضمام: | edsbas.72B6DF4 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1051/0004-6361/202038100 |
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