3D shape of asteroid (6) Hebe from VLT/SPHERE imaging: Implications for the origin of ordinary H chondrites

Autor: Christophe Dumas, Marco Delbo, Pierre Vernazza, J. Grice, Thierry Fusco, J. Berthier, Emmanuel Jehin, T. G. Müller, Josef Hanus, Michaël Gillon, Michael Marsset, F. Kugel, Raoul Behrend, Matti Viikinkoski, J. Caron, Sarah M. Sonnett, Bin Yang, Benoit Carry
Přispěvatelé: Astrophysics Research Centre [Belfast] (ARC), Queen's University [Belfast] (QUB), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), TMT Observatory, Astronomical Institute of Charles University, Charles University [Prague] (CU), Tampere University of Technology [Tampere] (TUT), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Max-Planck-Institut für Extraterrestrische Physik (MPE), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, The Open University [Milton Keynes] (OU), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Planetary Science Institute [Tucson] (PSI), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Tampere University, Mathematics, Research group: Inverse Problems, 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), TMT International Observatory, 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), Université de Genève = University of Geneva (UNIGE), Astrophysics Research Centre, Queen's University Belfast, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Astéroïdes, comètes, météores et éphémérides (ACME), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Astronomical Institute, Charles University, Department of Mathematics, Tampere University of Technology, Max-Planck-Institut fur extraterrestrische Physik, University of Liège, Open University, European Southern Observatory, ONERA, Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, CdR & CdL Group: Lightcurves of Minor Planets and Variable Stars
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Rotation period
010504 meteorology & atmospheric sciences
ASTEROIDE
FOS: Physical sciences
Context (language use)
Astrophysics
OPTIQUE ADAPTATIVE
01 natural sciences
VLT
MINOR PLANETS
Chondrite
0103 physical sciences
TECHNIQUES
111 Mathematics
010303 astronomy & astrophysics
0105 earth and related environmental sciences
Physics
Earth and Planetary Astrophysics (astro-ph.EP)
biology
METEORITES
Hebe
HIGH ANGULAR RESOLUTION
Astronomy and Astrophysics
Light curve
biology.organism_classification
ASTEROIDS INDIVIDUAL (6) HEBE
METEORS
[PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph]
METEOROIDS
Meteorite
13. Climate action
Space and Planetary Science
Asteroid
[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic
Asteroid belt
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Astrophysics - Earth and Planetary Astrophysics
Zdroj: Astronomy and Astrophysics-A&A
Astronomy and Astrophysics-A&A, EDP Sciences, 2017, 604, page 1-12. ⟨10.1051/0004-6361/201731021⟩
Astronomy & Astrophysics
Astronomy and Astrophysics-A&A, 2017, 604, page 1-12. ⟨10.1051/0004-6361/201731021⟩
Astronomy and Astrophysics-A&A, EDP Sciences, 2017, 604
ISSN: 0004-6361
DOI: 10.1051/0004-6361/201731021⟩
Popis: Context. The high-angular-resolution capability of the new-generation ground-based adaptive-optics camera SPHERE at ESO VLT allows us to assess, for the very first time, the cratering record of medium-sized (D~100-200 km) asteroids from the ground, opening the prospect of a new era of investigation of the asteroid belt's collisional history. Aims. We investigate here the collisional history of asteroid (6) Hebe and challenge the idea that Hebe may be the parent body of ordinary H chondrites, the most common type of meteorites found on Earth (~34% of the falls). Methods. We observed Hebe with SPHERE as part of the science verification of the instrument. Combined with earlier adaptive-optics images and optical light curves, we model the spin and three-dimensional (3D) shape of Hebe and check the consistency of the derived model against available stellar occultations and thermal measurements. Results. Our 3D shape model fits the images with sub-pixel residuals and the light curves to 0.02 mag. The rotation period (7.274 47 h), spin (343 deg,+47 deg), and volume-equivalent diameter (193 +/- 6km) are consistent with previous determinations and thermophysical modeling. Hebe's inferred density is 3.48 +/- 0.64 g.cm-3 , in agreement with an intact interior based on its H-chondrite composition. Using the 3D shape model to derive the volume of the largest depression (likely impact crater), it appears that the latter is significantly smaller than the total volume of close-by S-type H-chondrite-like asteroid families. Conclusions. Our results imply that (6) Hebe is not the most likely source of H chondrites. Over the coming years, our team will collect similar high-precision shape measurements with VLT/SPHERE for ~40 asteroids covering the main compositional classes, thus providing an unprecedented dataset to investigate the origin and collisional evolution of the asteroid belt.
Comment: 11 pages, 13 figures, accepted for publication in A&A
Databáze: OpenAIRE
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