[en] Planetary rings are observed not only around giant planets, but also around small bodies such as the Centaur Chariklo and the dwarf planet Haumea. Up to now, all known dense rings were located close enough to their parent bodies, being inside the Roche limit, where tidal forces prevent material with reasonable densities from aggregating into a satellite. Here we report observations of an inhomogeneous ring around the trans-Neptunian body (50000) Quaoar. This trans-Neptunian object has an estimated radius of 555 km and possesses a roughly 80-km satellite (Weywot) that orbits at 24 Quaoar radii. The detected ring orbits at 7.4 radii from the central body, which is well outside Quaoar's classical Roche limit, thus indicating that this limit does not always determine where ring material can survive. Our local collisional simulations show that elastic collisions, based on laboratory experiments, can maintain a ring far away from the body. Moreover, Quaoar's ring orbits close to the 1/3 spin-orbit resonance with Quaoar, a property shared by Chariklo's and Haumea's rings, suggesting that this resonance plays a key role in ring confinement for small bodies.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Morgado, B. E.; Federal University of Rio de Janeiro - Observatory of Valongo, Rio de Janeiro, Brazil, National Observatory/MCTI, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Sicardy, B.; LESIA, Observatory of Paris, University PSL, CNRS, UPMC, Sorbonne University, University of Paris Diderot, Sorbonne Paris City, Meudon, France
Braga-Ribas, F.; Federal University of Technology, Parana, Brazil
Ortiz, J. L.; Institute of Astrophysics at Andalucía, IAA-CSIC, Granada, Spain
Salo, H.; University of Oulu, Division of Astronomy
Vachier, F.; The Institute of Celestial Mechanics and Ephemeris Calculation (IMCCE), Observatory of Paris, PSL Research University, CNRS, Sorbonne University, UPMC University of Paris, University of Lille, Lille, France
Desmars, J.; The Institute of Celestial Mechanics and Ephemeris Calculation (IMCCE), Observatory of Paris, PSL Research University, CNRS, Sorbonne University, UPMC University of Paris, University of Lille, Lille, France, Polytechnic Institute of Advanced Sciences (IPSA), Ivry-sur-Seine, France
Pereira, C. L.; National Observatory/MCTI, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Santos-Sanz, P.; Institute of Astrophysics at Andalucía, IAA-CSIC, Granada, Spain
Sfair, R.; Institute for Astronomy and Astrophysics, Eberhard Karls University of Tübingen, Tübingen, Germany, Orbital Dynamics and Planetology Group, UNESP - São Paulo State University, Guaratinguetá, Brazil
de Santana, T.; LESIA, Observatory of Paris, University PSL, CNRS, UPMC, Sorbonne University, University of Paris Diderot, Sorbonne Paris City, Meudon, France, Orbital Dynamics and Planetology Group, UNESP - São Paulo State University, Guaratinguetá, Brazil
Assafin, M.; Federal University of Rio de Janeiro - Observatory of Valongo, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Vieira-Martins, R.; National Observatory/MCTI, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Gomes-Júnior, A. R.; Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil, Orbital Dynamics and Planetology Group, UNESP - São Paulo State University, Guaratinguetá, Brazil, Institute of Physics, Federal University of Uberlândia, Uberlândia, Brazil
Margoti, G.; Federal University of Technology, Parana, Brazil
Dhillon, V. S.; University of Sheffield, Department of Physics and Astronomy, -
Fernández-Valenzuela, E.; University of Central Florida
Broughton, J.; Reedy Creek Observatory, Gold Coast, Queensland, Australia, Trans-Tasman Occultation Alliance (TTOA), Wellington, New Zealand
Bradshaw, J.; Samford Valley Observatory (Q79), Brisbane, Queensland, Australia
Langersek, R.; Algester Astronomical Observatory, Brisbane, Queensland, Australia
Benedetti-Rossi, G.; Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil, Orbital Dynamics and Planetology Group, UNESP - São Paulo State University, Guaratinguetá, Brazil
Souami, D.; LESIA, Observatory of Paris, University PSL, CNRS, UPMC, Sorbonne University, University of Paris Diderot, Sorbonne Paris City, Meudon, France, Observatory of the Côte d'Azur, Lagrange Laboratory UMR7293 CNRS, Nice, France, naXys, University of Namur, Namur, Belgium
Holler, B. J.; Space Telescope Science Institute, Baltimore, Maryland
Kretlow, M.; Institute of Astrophysics at Andalucía, IAA-CSIC, Granada, Spain, International Occultation Timing Association / European Section, Hannover, Germany, International Amateur Observatory e.V. (IAS), Mittenwalde, Germany
Boufleur, R. C.; National Observatory/MCTI, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Camargo, J. I. B.; National Observatory/MCTI, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Duffard, R.; Institute of Astrophysics at Andalucía, IAA-CSIC, Granada, Spain
Beisker, W.; International Occultation Timing Association / European Section, Hannover, Germany, International Amateur Observatory e.V. (IAS), Mittenwalde, Germany
Morales, N.; Institute of Astrophysics at Andalucía, IAA-CSIC, Granada, Spain
Lecacheux, J.; LESIA, Observatory of Paris, University PSL, CNRS, UPMC, Sorbonne University, University of Paris Diderot, Sorbonne Paris City, Meudon, France
Rommel, F. L.; National Observatory/MCTI, Rio de Janeiro, Brazil, Interinstitutional e-Astronomy Laboratory (LIneA), Rio de Janeiro, Brazil
Herald, D.; Trans-Tasman Occultation Alliance (TTOA), Wellington, New Zealand
Benz, W.; University of Bern, Physics Institute, University of Bern, Physics Institute
Jehin, Emmanuel ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa)
Jankowsky, F.; Heidelberg-Königstuhl State Observatory, Heidelberg, Germany
Marsh, T. R.; University of Warwick, Department of Physics
Littlefair, S. P.; University of Sheffield, Department of Physics and Astronomy
Bruno, G.; Astronomical Observatory of Catania
Pagano, I.; Astronomical Observatory of Catania
Brandeker, A.; AlbaNova University Center
Collier-Cameron, A.; Centre for Exoplanet Science, SUPA School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, UK
Florén, H. G.; AlbaNova University Center
Hara, N.; Astronomical Observatory at the University of Geneva, Versoix, Switzerland
Olofsson, G.; AlbaNova University Center
Wilson, T. G.; Centre for Exoplanet Science, SUPA School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, UK
Benkhaldoun, Z.; Oukaimeden Observatory, High Energy Physics and Astrophysics Laboratory, FSSM, Cadi Ayyad University, Marrakech, Morocco
Busuttil, R.; Open University, Department of Physical Sciences
Burdanov, A.; MIT, Department of Earth and Planetary Science
Ferrais, Marin ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa) ; Laboratory of Astrophysics of Marseille, University of Aix Marseille, CNRS, CNES, Marseille, France
Gault, D.; Trans-Tasman Occultation Alliance (TTOA), Wellington, New Zealand
Gillon, Michaël ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO)
Hanna, W.; Trans-Tasman Occultation Alliance (TTOA), Wellington, New Zealand
Kerr, S.; Trans-Tasman Occultation Alliance (TTOA), Wellington, New Zealand, Astronomical Association of Queensland, Pimpama, Queensland, Australia
Kolb, U.; Open University, Department of Physical Sciences
Nosworthy, P.; Trans-Tasman Occultation Alliance (TTOA), Wellington, New Zealand
Sebastian, D.; University of Birmingham, School of Physics and Astronomy
Snodgrass, C.; Royal Observatory Edinburgh
Teng, J. P.; AGORA Observatory of Makes, AGORA, La Rivière, France
de Wit, J.; MIT, Department of Earth and Planetary Science
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