/ftp/cats/i/259



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I/259           The Tycho-2 Catalogue              (Hog+ 2000)
The following files can be converted to FITS (extension .fit .fgz or .fiZ)
	tyc2.dat suppl_1.dat, suppl_2.dat index.dat
Note that most of the data files are gzipped; the uncompressed version can 
	be retrieved either using the gunzip program, or by omitting the
	.gz extension (decompression on the fly, but increases the traffic)
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Query from: http://vizier.cds.unistra.fr/cgi-bin/VizieR?-source=I/259
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drwxr-xr-x 317 cats archive 8192 Feb 28 11:16 [Up] drwxr-xr-x 2 cats archive 4096 Jul 25 2023 [TAR file] -rw-r--r-- 1 cats archive 689 Dec 19 2022 .message -rw-r--r-- 1 cats archive 16773 Sep 8 2002 ReadMe -rw-r--r-- 1 cats archive 1006 Sep 19 2007 +footg5.gif -rw-r--r-- 1 cats archive 14263 May 6 2012 +footg5.png -rw-r--r-- 1 cats archive 2135 Mar 5 2008 +footg8.gif -rw-r--r-- 1 cats archive 226720 May 6 2012 +footg8.png -r--r--r-- 1 cats archive 428724 Jan 20 2000 guide.pdf -r--r--r-- 1 cats archive 207884 Feb 5 2000 guide.ps.gz [Uncompressed] -rw-r--r-- 1 cats archive 671712 Feb 14 2000 suppl_1.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 43037 Feb 5 2000 suppl_2.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8407799 Feb 6 2000 tyc2.dat.00.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8375063 Feb 6 2000 tyc2.dat.01.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8351549 Feb 6 2000 tyc2.dat.02.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8426693 Feb 6 2000 tyc2.dat.03.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8487663 Feb 6 2000 tyc2.dat.04.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8247134 Feb 6 2000 tyc2.dat.05.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8039302 Feb 6 2000 tyc2.dat.06.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8129883 Feb 6 2000 tyc2.dat.07.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8224049 Feb 6 2000 tyc2.dat.08.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8424804 Feb 6 2000 tyc2.dat.09.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8512497 Feb 6 2000 tyc2.dat.10.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8497732 Feb 6 2000 tyc2.dat.11.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8350212 Feb 6 2000 tyc2.dat.12.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8360023 Feb 6 2000 tyc2.dat.13.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8472405 Feb 6 2000 tyc2.dat.14.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8455626 Feb 6 2000 tyc2.dat.15.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8416328 Feb 6 2000 tyc2.dat.16.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8171031 Feb 6 2000 tyc2.dat.17.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8077674 Feb 6 2000 tyc2.dat.18.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 8195964 Feb 6 2000 tyc2.dat.19.gz [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe : I/259 The Tycho-2 Catalogue (Hog+ 2000) ================================================================================ The Tycho-2 Catalogue of the 2.5 Million Brightest Stars Hog E., Fabricius C., Makarov V.V., Urban S., Corbin T., Wycoff G., Bastian U., Schwekendiek P., Wicenec A. <Astron. Astrophys. 355, L27 (2000)> =2000A&A...355L..27H ================================================================================ ADC_Keywords: Positional data ; Proper motions ; Surveys ; Photometry ; Stars, double and multiple Mission_Name: Hipparcos Keywords: astrometry - stars: fundamental parameters - catalogs Abstract: The Tycho-2 Catalogue is an astrometric reference catalogue containing positions and proper motions as well as two-colour photometric data for the 2.5 million brightest stars in the sky. The Tycho-2 positions and magnitudes are based on precisely the same observations as the original Tycho Catalogue (hereafter Tycho-1; see Cat. I/239)) collected by the star mapper of the ESA Hipparcos satellite, but Tycho-2 is much bigger and slightly more precise, owing to a more advanced reduction technique. Components of double stars with separations down to 0.8 arcsec are included. Proper motions precise to about 2.5 mas/yr are given as derived from a comparison with the Astrographic Catalogue and 143 other ground-based astrometric catalogues, all reduced to the Hipparcos celestial coordinate system. Tycho-2 supersedes in most applications Tycho-1, as well as the ACT (Cat. I/246) and TRC (Cat. I/250) catalogues based on Tycho-1. Supplement-1 lists stars from the Hipparcos and Tycho-1 Catalogues which are not in Tycho-2. Supplement-2 lists 1146 Tycho-1 stars which are probably either false or heavily disturbed. For more information, please consult the Tycho-2 home page: http://www.astro.ku.dk/~erik/Tycho-2 Catalogue Characteristics: The principal characteristics of the Tycho-2 Catalogue are summarized below. By means of proper motions the positions are transferred to the year 2000.0, the epoch of the catalogue. The median values of internal standard errors are given. ------------------------------------------------------------ Mean satellite observation epoch  J1991.5 Epoch of the Tycho-2 Catalogue J2000.0 Reference system ICRS coincidence with ICRS (1) +/-0.6 mas deviation from inertial (1) +/-0.25 mas/yr Number of entries 2,539,913 Astrometric standard errors (2) V_T_ < 9 mag 7 mas all stars, positions 60 mas all stars, proper motions 2.5 mas/yr Photometric std. errors (3) on V_T_ V_T_ < 9 mag 0.013 mag all stars 0.10 mag Star density b= 0 deg 150 stars/sq.deg. b= +/-30 deg 50 stars/sq.deg. b= +/-90 deg 25 stars/sq.deg. Completeness to 90 per cent V   11.5 mag Completeness to 99 per cent V   11.0 mag Number of Tycho observations  300 10^6^ ------------------------------------------------------------ Note (1): about all 3 axes Note (2): ratio of external to internal standard errors is  1.0 for positions and for proper motions. Systematic errors are less than 1 mas and 0.5 mas/yr Note (3): ratio of photometric external to internal standard errors at V_T_ > 9 mag is below 1.5 ------------------------------------------------------------