/ftp/cats/I/238A



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I/238A      Yale Trigonometric Parallaxes, Fourth Edition  (van Altena+ 1995)
The following files can be converted to FITS (extension .fit .fgz or .fiZ)
	picat.dat source.dat errata.dat
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Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/238A
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drwxr-xr-x 317 cats archive 8192 Feb 28 11:16 [Up] drwxr-xr-x 4 cats archive 4096 Jan 13 2023 [TAR file] -rw-r--r-- 1 cats archive 482 Dec 19 2022 .message -r--r--r-- 1 cats archive 9776 Feb 8 2021 ReadMe -rw-r--r-- 1 cats archive 1581 Feb 8 2021 +footg5.gif -rw-r--r-- 1 cats archive 22121 Feb 8 2021 +footg8.gif -r--r--r-- 1 cats archive 49091 Aug 11 2001 correct.htm.gz [Uncompressed] -rw-r--r-- 1 cats archive 42464 Aug 11 2001 errata.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 1173412 Nov 20 2017 picat.dat [txt] [txt.gz] [fits] [fits.gz] [html] -r--r--r-- 1 cats archive 1692 Aug 11 2001 source.dat.gz [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe : I/238A Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995) ================================================================================ The General Catalogue of Trigonometric Stellar Parallaxes, Fourth Edition Van Altena W.F., Lee J.T., Hoffleit E.D. <Yale University Observatory (1995)> =1995GCTP..C......0V ================================================================================ ADC_Keywords: Parallaxes, trigonometric Description: This is a completely revised and enlarged edition of the General Catalogue of Trigonometric Stellar Parallaxes containing 15,994 parallaxes for 8,112 stars published before the end of 1995. In this Fourth Edition, 1,722 (27%) new stars have been added to those contained in the previous edition by Jenkins (1963). The mode of the parallax accuracy for the newly added stars (0.004" s.e.) is considerably better than in the previous editions (about 0.016"). Approximately 2300 stars are not in the Hipparcos Catalog. The catalog contains equatorial coordinates in the system of the FK4 for 1900, the total proper motion and its position angle, the weighted average absolute parallax and its standard error, the number of parallax observations, quality of interagreement of the different values, the visual magnitude and various cross identifications with other catalogs. Auxiliary information is listed, including UBV photometry, MK spectral types, data on the variability and binary nature of the stars, and miscellaneous information to aid in determining the reliability of the data. Introduction: The 1900 equinox has been maintained to avoid assigning yet another star number and avoid potential errors, since the 1900 based numbers have been used in the Notes and elsewhere in the Catalogue. For each star, the printed catalog contains a reference to the source of publication of the individual parallax The relative parallaxes are corrected to absolute parallax using newly computed corrections that are based on an improved model of the Galaxy. In the Introduction to the printed Catalogue, an analysis of the resulting absolute parallaxes has been made to study the accidental and systematic errors of the parallaxes. Those results provide a "system" for the Catalogue which then yields weighted absolute parallaxes for each star. A preliminary version I/174 of this catalog was previously archived in the Astronomical Data Centers and was included on the first ADC CD-ROM. In this final version the authors have revised the weighting system, and included newly published parallaxes, photometry and spectral types for most of the stars. The weighted mean parallaxes of many stars will be found to differ from those in the preliminary version due to changes in the weighting system, revisions to the default reference star magnitudes and the addition of new parallaxes. The file "errata.dat", added in August 2001, was supplied by Erkki U. Vilkki; it contains rectifications and additions to the General Catalogue of Trigonometric Stellar Parallaxes. Majority of additions are from the Lowell proper motion survey. In the double star information designations were rectified according to the last edition of the Washington Double Star WDS catalog. The following CD-ROMs were used: ADS Selected Astronomical Catalogs, Vol. 1, Vol. 2, and Vol. 3 (FITS versions), the Guide Star Catalog (version 1.1), HyperSky Data Bank, and Guide.