GaiaEarly Data Release 3

Astronomy and Astrophysics, vol. 649, pp. A9

Abstract

Context.GaiaEarly Data Release 3 (GaiaEDR3) provides accurate astrometry for about 1.6 million compact (QSO-like) extragalactic sources, 1.2 million of which have the best-quality five-parameter astrometric solutions. Aims.The proper motions of QSO-like sources are used to reveal a systematic pattern due to the acceleration of the solar systembarycentre with respect to the rest frame of the Universe. Apart from being an important scientific result by itself, the acceleration measured in this way is a good quality indicator of theGaiaastrometric solution. Methods.Theeffect of the acceleration was obtained as a part of the general expansion of the vector field of proper motions in vector spherical harmonics (VSH). Various versions of the VSH fit and various subsets of the sources were tried and compared to get the most consistent result and a realistic estimate of its uncertainty. Additional tests with theGaiaastrometric solution were used to get a better idea of the possible systematic errors in the estimate. Results.Our best estimate of the acceleration based onGaiaEDR3 is (2.32 ± 0.16) × 10−10m s−2(or 7.33 ±0.51 km s−1Myr−1) towardsα= 269.1° ± 5.4°,δ= −31.6° ± 4.1°, corresponding to a proper motion amplitude of 5.05 ±0.35μas yr−1. This is in good agreement with the acceleration expected from current models of the Galactic gravitational potential. We expect that futureGaiadata releases will provide estimates of the acceleration with uncertainties substantially below 0.1μas yr−1.

Authors 100

1. S. A. Klioner

   Technische Universität Dresden

   Affiliation as printed

   Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany

2. F. Mignard

   Centre National de la Recherche Scientifique · Université Côte d'Azur · Lagrange Laboratory · Observatoire de la Côte d’Azur

   Affiliation as printed

   Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France

   Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Bd de l'Observatoire, CS 34229, 06304 Nice Cedex 4, France

3. L. Lindegren

   Lund University

   Affiliation as printed

   Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden

4. U. Bastian

   Heidelberg University

   Affiliation as printed

   Astronomisches Rechen-Institut, Zentrum fôr Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany

5. P. J. McMillan

   Lund University

   Affiliation as printed

   Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden

6. J. Hernández

   European Space Agency · European Space Astronomy Centre

   Affiliation as printed

   European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

7. D. Hobbs

   Lund University

   Affiliation as printed

   Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden

8. M. Ramos-Lerate

   European Space Agency · European Space Astronomy Centre

   Affiliation as printed

   Vitrociset Belgium for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

9. M. Biermann

   Heidelberg University

   Affiliation as printed

   Astronomisches Rechen-Institut, Zentrum fôr Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany

10. A. Bombrun

    European Space Agency · European Space Astronomy Centre

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    HE Space Operations BV for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

11. A. de Torres

    European Space Agency · European Space Astronomy Centre

    Affiliation as printed

    HE Space Operations BV for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

12. E. Gerlach

    Technische Universität Dresden

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    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany

13. R. Geyer

    Technische Universität Dresden

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    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany

14. T. Hilger

    Technische Universität Dresden

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    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany

15. Uwe Lammers

    European Space Agency · European Space Astronomy Centre

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    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

16. Hagen Steidelmüller

    Technische Universität Dresden

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    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany

17. C. A. Stephenson

    European Space Agency

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    Telespazio Vega UK Ltd for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

18. A. G. A. Brown Aachen Leiden Observatory

    Leiden University · Leiden Observatory

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    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands

19. Antonella Vallenari

    Osservatorio Astronomico di Padova

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    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy

20. T. Prusti

    European Space Agency · European Space Research and Technology Centre

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    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201AZ Noordwijk, The Netherlands

21. J. H. J. de Bruijne

    European Space Agency · European Space Research and Technology Centre

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    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201AZ Noordwijk, The Netherlands

22. C. Babusiaux

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

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    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France

    Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

23. O. L. Creevey

    Centre National de la Recherche Scientifique · Université Côte d'Azur · Lagrange Laboratory · Observatoire de la Côte d’Azur

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    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France

    Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Bd de l'Observatoire, CS 34229, 06304 Nice Cedex 4, France

24. Dafydd Wyn Evans

    University of Cambridge

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    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

25. L. Eyer

    University of Geneva

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    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland

26. A. Hutton

    European Space Agency · European Space Astronomy Centre

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    Aurora Technology for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

27. F. A. Jansen

    European Space Agency · European Space Research and Technology Centre

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    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201AZ Noordwijk, The Netherlands

28. C. Jordi

    Institut de Ciències del Cosmos · Universitat de Barcelona

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    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain

29. X. Luri

    Institut de Ciències del Cosmos · Universitat de Barcelona

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    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain

30. C. Panem

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

31. D. Pourbaix

    Université Libre de Bruxelles · Fund for Scientific Research

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    F.R.S.-FNRS, Rue d'Egmont 5, 1000 Brussels, Belgium

    Institut d'Astronomie et d'Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium

32. Sofia Randich

    Arcetri Astrophysical Observatory

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    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy

33. P. Sartoretti

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation

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    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France

34. Caroline Soubiran

    Centre National de la Recherche Scientifique · Laboratoire d'Astrophysique de Bordeaux

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    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France

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35. N. A. Walton

    University of Cambridge

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    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

36. F. Arenou

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation

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    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France

37. C. A. L. Bailer‐Jones

    Max Planck Institute for Astronomy

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    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

38. Mark S. Cropper

    University College London

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    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK

39. R. Drimmel

    Osservatorio Astrofisico di Torino

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    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese (TO), Italy

40. David Katz

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation

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    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France

41. M. G. Lattanzi

    Osservatorio Astrofisico di Torino · University of Turin

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    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese (TO), Italy

    University of Turin, Department of Physics, Via Pietro Giuria 1, 10125 Torino, Italy

42. Floor van Leeuwen

    University of Cambridge

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    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

43. J. Bakker

    European Space Agency · European Space Astronomy Centre

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    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

44. J. Castañeda

    Institut de Ciències del Cosmos · Universitat de Barcelona

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    DAPCOM for Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain

45. F. De Angeli

    University of Cambridge

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    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

46. Christine Ducourant

    Centre National de la Recherche Scientifique · Laboratoire d'Astrophysique de Bordeaux

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    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France

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47. C. Fabricius

    Institut de Ciències del Cosmos · Universitat de Barcelona

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    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain

48. M. Fouesneau

    Max Planck Institute for Astronomy

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    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

49. Y. Frémat

    Royal Observatory of Belgium

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    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium

50. R. Guerra

    European Space Agency · European Space Astronomy Centre

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    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

51. A. Guerrier

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

52. Julie Guiraud

    Centre National d'Études Spatiales

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53. A. Jean-Antoine Piccolo

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

54. E. Masana

    Institut de Ciències del Cosmos · Universitat de Barcelona

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    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain

55. R. Messineo
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    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy

56. N. Mowlavï

    University of Geneva

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    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland

57. C. Nicolas

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

58. K. Nienartowicz

    University of Geneva

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    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland

    Sednai Sàrl, Geneva, Switzerland

    Department of Astronomy, University of Geneva, Chemin d'Ecogia 16, 1290 Versoix, Switzerland

59. F. Pailler

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

60. P. Panuzzo

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation

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    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France

61. F. Riclet

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

62. W. Roux

    Centre National d'Études Spatiales

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    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France

63. G. M. Seabroke

    University College London

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    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK

64. R. Sordo

    Osservatorio Astronomico di Padova

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    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy

65. P. Tanga

    Centre National de la Recherche Scientifique · Université Côte d'Azur · Lagrange Laboratory · Observatoire de la Côte d’Azur

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    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France

    Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Bd de l'Observatoire, CS 34229, 06304 Nice Cedex 4, France

66. Frédéric Thévenin

    Centre National de la Recherche Scientifique · Université Côte d'Azur · Lagrange Laboratory · Observatoire de la Côte d’Azur

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    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France

    Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Bd de l'Observatoire, CS 34229, 06304 Nice Cedex 4, France

67. G. Gracia-Abril

    Heidelberg University · European Space Astronomy Centre

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    Astronomisches Rechen-Institut, Zentrum fôr Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany

    Gaia DPAC Project Office, ESAC, Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

68. J. Portell

    Institut de Ciències del Cosmos · Universitat de Barcelona

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    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain

69. D. Teyssier

    European Space Agency

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    Telespazio Vega UK Ltd for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

70. M. Altmann

    Centre National de la Recherche Scientifique · Heidelberg University · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Systèmes de Référence Temps-Espace · Laboratoire Temps Espace

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    Astronomisches Rechen-Institut, Zentrum fôr Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany

    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France

    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l'Observatoire 75014 Paris, France

71. R. Andrae

    Max Planck Institute for Astronomy

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    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

72. I. Bellas-Velidis

    National Observatory of Athens

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    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece

73. K. Benson

    University College London

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    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK

74. J. Berthier

    Centre National de la Recherche Scientifique · Université de Lille · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Institut de Mécanique Céleste et de Calcul des Éphémérides

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75. R. Blomme

    Royal Observatory of Belgium

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76. E. Brugaletta

    Osservatorio Astrofisico di Catania

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77. P. W. Burgess

    University of Cambridge

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    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

78. G. Busso

    University of Cambridge

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    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

79. B. Carry

    Centre National de la Recherche Scientifique · Université Côte d'Azur · Lagrange Laboratory · Observatoire de la Côte d’Azur

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80. A. Cellino

    Osservatorio Astrofisico di Torino

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    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese (TO), Italy

81. N. Cheek

    European Space Agency · European Space Astronomy Centre

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    Serco Gestión de Negocios for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

82. G. Clementini

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics

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83. Y. Damerdji

    University of Liège · Centre de Recherche en Astronomie Astrophysique et Géophysique

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    CRAAG – Centre de Recherche en Astronomie, Astrophysique et Géophysique, Route de l’Observatoire Bp 63 Bouzareah 16340 Algiers, Algeria

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84. M. Davidson

    Royal Observatory · University of Edinburgh

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    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK

85. L. Delchambre

    University of Liège

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    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium

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86. Aldo Dell’Oro

    Arcetri Astrophysical Observatory

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    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy

87. J. Fernández-Hernández

    European Space Agency · European Space Astronomy Centre

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    ATG Europe for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

88. L. Galluccio

    Centre National de la Recherche Scientifique · Université Côte d'Azur · Lagrange Laboratory · Observatoire de la Côte d’Azur

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    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France

    Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Bd de l'Observatoire, CS 34229, 06304 Nice Cedex 4, France

89. P. García-Lario

    European Space Agency · European Space Astronomy Centre

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    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

90. M. Garcia-Reinaldos

    European Space Agency · European Space Astronomy Centre

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    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

91. J. González-Núñez

    European Space Agency · European Space Astronomy Centre · Universidade de Vigo

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    ETSE Telecomunicación, Universidade de Vigo, Campus Lagoas-Marcosende, 36310 Vigo, Galicia, Spain

    Serco Gestión de Negocios for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain

92. E. Gosset

    University of Liège · Fund for Scientific Research

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    F.R.S.-FNRS, Rue d’Egmont 5, 1000 Brussels, Belgium

    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium

    F.R.S.-FNRS, Rue d'Egmont 5, 1000 Brussels, Belgium

    Institut d'Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium

93. R. Haigron

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Galaxies, Etoiles, Physique et Instrumentation

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    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France

94. J. L. Halbwachs

    Centre National de la Recherche Scientifique · Observatoire astronomique de Strasbourg · Université de Strasbourg

    Affiliation as printed

    Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France

    Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, 11 rue de l'Université, 67000 Strasbourg, France

95. N. C. Hambly

    Royal Observatory · University of Edinburgh

    Affiliation as printed

    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK

96. Diana L. Harrison

    University of Cambridge

    Affiliation as printed

    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

    Kavli Institute for Cosmology Cambridge, Institute of Astronomy, Madingley Road, Cambridge, CB3 0HA, USA

97. D. Hatzidimitriou

    National and Kapodistrian University of Athens

    Affiliation as printed

    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece

98. U. Heiter

    Uppsala University

    Affiliation as printed

    Observational Astrophysics, Division of Astronomy and Space Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden

99. Daniel Hestroffer

    Centre National de la Recherche Scientifique · Université de Lille · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Institut de Mécanique Céleste et de Calcul des Éphémérides

    Affiliation as printed

    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France

100. S. T. Hodgkin

     University of Cambridge

     Affiliation as printed

     Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK