/ftp/cats/I/250



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I/250               The Tycho Reference Catalogue       (Hog+ 1998)
The following files can be converted to FITS (extension .fit .fgz or .fiZ)
	catalog.dat index .dat
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Query from: http://vizier.cds.unistra.fr/cgi-bin/VizieR?-source=I/250
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drwxr-xr-x 317 cats archive 8192 Feb 28 11:16 [Up] drwxr-xr-x 2 cats archive 315 Jul 25 2023 [TAR file] -rw-r--r-- 1 cats archive 462 Dec 19 2022 .message -r--r--r-- 1 cats archive 8220 Dec 1 2008 ReadMe -rw-r--r-- 1 cats archive 1006 Sep 19 2007 +footg5.gif -rw-r--r-- 1 cats archive 15163 May 6 2012 +footg5.png -rw-r--r-- 1 cats archive 2104 Mar 5 2008 +footg8.gif -rw-r--r-- 1 cats archive 211404 May 6 2012 +footg8.png -rw-r--r-- 1 cats archive 44859188 May 26 1998 catalog.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe : I/250 The Tycho Reference Catalogue (Hog+ 1998) ================================================================================ The Tycho Reference Catalogue Hog E., Kuzmin A., Bastian U., Fabricius C., Kuimov K., Lindegren L., Makarov V.V., Roeser S. <Astron. Astrophys. 335, L65 (1998)> =1998A&A...335L..65H ================================================================================ ADC_Keywords: Positional data; Proper motions ; Astrographic zones; Historical catalog; Photographic catalog; Surveys; Cross identifications Mission_Name: Hipparcos Keywords: astrometry - reference catalogues - proper motions - Astrographic Catalogue - Tycho Catalogue Abstract: The Tycho Reference Catalogue (TRC) contains high-quality positions and proper motions for 990182 stars of the Tycho Catalogue. The proper motions were derived from Tycho positions and Astrographic Catalogue positions reduced to the Hipparcos system. The median accuracy of the TRC position components is 40 mas at J1991.25. The median accuracy of the proper motion is about 2.5 mas/yr. Systematic errors are less than about 1.0 mas(/yr). The quality of the proper motions in TRC is assessed by comparison with the Hipparcos and Tycho Catalogues. Comparison with the recent ACT Catalogue which is based on an independent reduction of the same observations as used for constructing the TRC is reported.