VizieR Online Data Catalog: The Tycho-2 Catalogue (Hog+ 2000)

  • E. Hog (Creator)
  • C. Fabricius (Creator)
  • V.~V. Makarov (Creator)
  • S. Urban (Creator)
  • T. Corbin (Creator)
  • G. Wycoff (Creator)
  • U. Bastian (Creator)
  • P. Schwekendiek (Creator)
  • Andreas Wicenec (Creator)



The Tycho-2 Catalogue is an astrometric reference catalogue containingpositions and proper motions as well as two-colour photometric data forthe 2.5 million brightest stars in the sky. The Tycho-2 positions andmagnitudes are based on precisely the same observations as the originalTycho Catalogue (hereafter Tycho-1; see Cat. )) collectedby the star mapper of the ESA Hipparcos satellite, but Tycho-2 is muchbigger and slightly more precise, owing to a more advanced reductiontechnique. Components of double stars with separations down to 0.8arcsec are included. Proper motions precise to about 2.5 mas/yr aregiven as derived from a comparison with the Astrographic Catalogue and143 other ground-based astrometric catalogues, all reduced to theHipparcos celestial coordinate system. Tycho-2 supersedes in mostapplications Tycho-1, as well as the ACT (Cat. ) and TRC(Cat. ) catalogues based on Tycho-1. Supplement-1 listsstars from the Hipparcos and Tycho-1 Catalogues which are not inTycho-2. Supplement-2 lists 1146 Tycho-1 stars which are probably eitherfalse or heavily disturbed. For more information, please consult theTycho-2 home page: (4 data files).
Date made availableJan 2000
PublisherSAO/NASA Astrophysics Data System (ADS)

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