Publication Date:
2015-10-10
Description:
In the 1980s, excess infrared emission was discovered around main-sequence stars; subsequent direct-imaging observations revealed orbiting disks of cold dust to be the source. These 'debris disks' were thought to be by-products of planet formation because they often exhibited morphological and brightness asymmetries that may result from gravitational perturbation by planets. This was proved to be true for the beta Pictoris system, in which the known planet generates an observable warp in the disk. The nearby, young, unusually active late-type star AU Microscopii hosts a well-studied edge-on debris disk; earlier observations in the visible and near-infrared found asymmetric localized structures in the form of intensity variations along the midplane of the disk beyond a distance of 20 astronomical units. Here we report high-contrast imaging that reveals a series of five large-scale features in the southeast side of the disk, at projected separations of 10-60 astronomical units, persisting over intervals of 1-4 years. All these features appear to move away from the star at projected speeds of 4-10 kilometres per second, suggesting highly eccentric or unbound trajectories if they are associated with physical entities. The origin, localization, morphology and rapid evolution of these features are difficult to reconcile with current theories.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Boccaletti, Anthony -- Thalmann, Christian -- Lagrange, Anne-Marie -- Janson, Markus -- Augereau, Jean-Charles -- Schneider, Glenn -- Milli, Julien -- Grady, Carol -- Debes, John -- Langlois, Maud -- Mouillet, David -- Henning, Thomas -- Dominik, Carsten -- Maire, Anne-Lise -- Beuzit, Jean-Luc -- Carson, Joseph -- Dohlen, Kjetil -- Engler, Natalia -- Feldt, Markus -- Fusco, Thierry -- Ginski, Christian -- Girard, Julien H -- Hines, Dean -- Kasper, Markus -- Mawet, Dimitri -- Menard, Francois -- Meyer, Michael R -- Moutou, Claire -- Olofsson, Johan -- Rodigas, Timothy -- Sauvage, Jean-Francois -- Schlieder, Joshua -- Schmid, Hans Martin -- Turatto, Massimo -- Udry, Stephane -- Vakili, Farrokh -- Vigan, Arthur -- Wahhaj, Zahed -- Wisniewski, John -- England -- Nature. 2015 Oct 8;526(7572):230-2. doi: 10.1038/nature15705.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉LESIA, Observatoire de Paris, CNRS, Universite Paris Diderot, Universite Pierre et Marie Curie, 5 place Jules Janssen, 92190 Meudon, France. ; ETH Zurich, Institute for Astronomy, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich, Switzerland. ; Universite Grenoble Alpes, IPAG, F-38000 Grenoble, France. ; CNRS, IPAG, F-38000 Grenoble, France. ; Department of Astronomy, Stockholm University, SE-106 91 Stockholm, Sweden. ; Max-Planck-Institut fur Astronomie, Konigstuhl 17, D-69117 Heidelberg, Germany. ; Steward Observatory, 933 North Cherry Avenue, The University of Arizona, Tucson, Arizona 85721, USA. ; European Southern Observatory (ESO), Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago, Chile. ; Eureka Scientific, 2452 Delmer, Suite 100, Oakland, California 96002, USA. ; Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218, USA. ; Centre de Recherche Astrophysique de Lyon, (CNRS/ENS-L/Universite Lyon 1), 9 avenue Charles Andre, 69561 Saint-Genis-Laval, France. ; Aix Marseille Universite, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, 13388 Marseille, France. ; University of Amsterdam, Anton Pannekoek Institute for Astronomy, Science Park 904 1098 XH Amsterdam, The Netherlands. ; INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy. ; Department of Physics and Astronomy, College of Charleston, South Carolina, 29424, USA. ; ONERA-The French Aerospace Laboratory, 92322 Chatillon, France. ; Sterrewacht Leiden, PO Box 9513, Niels Bohrweg 2, NL-2300RA Leiden, The Netherlands. ; European Southern Observatory (ESO), Karl Schwarzschild Strasse 2, 85748 Garching bei Munchen, Germany. ; Department of Astronomy, California Institute of Technology, 1200 East California Boulevard, MC 249-17, Pasadena, California 91125, USA. ; UMI-FCA, CNRS/INSU France (UMI 3386), and Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Correo Central, Santiago, Chile. ; Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington DC 20015, USA. ; NASA Ames Research Center, Space Science and Astrobiology Division, MS 245-6, Moffett Field, California 94035, USA. ; Observatoire de Geneve, University of Geneva, 51 Chemin des Maillettes, 1290 Versoix, Switzerland. ; Laboratoire J.-L. Lagrange, Observatoire de la Cote d'Azur (OCA), Universite de Nice-Sophia Antipolis (UNS), CNRS, Campus Valrose, 06108 Nice Cedex 2, France. ; Department of Physics and Astronomy, University of Oklahoma, 440 West Brooks Street, Norman, Oklahoma 73019, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26450055" target="_blank"〉PubMed〈/a〉
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
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Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
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