/ftp/cats/I/340



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I/340                  UCAC5 Catalogue                         (Zacharias+ 2017)
The following files can be converted to FITS (extension .fit or fit.gz)
	ucac5.sam
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Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/340
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drwxr-xr-x 317 cats archive 8192 Feb 28 11:16 [Up] drwxr-xr-x 4 cats archive 4096 Dec 19 22:48 [TAR file] -rw-r--r-- 1 cats archive 459 Dec 19 16:53 .message -r--r--r-- 1 cats archive 5983 Apr 10 2018 ReadMe drwxr-xr-x 3 cats archive 25 Mar 16 2017 UCAC5 -rw-r--r-- 1 cats archive 1745 Dec 19 16:53 +footg5.gif -rw-r--r-- 1 cats archive 7549 Dec 19 16:54 +footg5.png -rw-r--r-- 1 cats archive 12884 Dec 19 16:53 +footg8.gif -rw-r--r-- 1 cats archive 50492 Dec 19 16:54 +footg8.png -r--r--r-- 1 cats archive 29267 Mar 13 2017 readmeU5.txt -rw-r--r-- 1 cats archive 10823040 Aug 22 2022 tab_1340_1_I_340_ucac5.moc.fits -r--r--r-- 1 cats archive 162000 Mar 15 2017 ucac5.sam
Beginning of ReadMe : I/340 UCAC5 Catalogue (Zacharias+ 2017) ================================================================================ UCAC5: New Proper Motions using Gaia DR1. Zacharias N., Finch C., Frouard J. <Astron. J., 153, 166 (2017)> =2017yCat.1340....0Z =2017AJ....153..166Z ================================================================================ ADC_Keywords: Surveys ; Positional data ; Proper motions Keywords: astrometry, proper motions Abstract: New astrometric reductions of the US Naval Observatory CCD Astrograph Catalog (UCAC) all-sky observations were performed from first principles using the TGAS stars in the 8 to 11 magnitude range as reference star catalog. Significant improvements in the astrometric solutions were obtained and the UCAC5 catalog of mean positions at a mean epoch near 2001 was generated. By combining UCAC5 with Gaia DR1 data new proper motions on the Gaia coordinate system for over 107 million stars were obtained with typical accuracies of 1 to 2mas/yr (R=11 to 15mag), and about 5mas/yr at 16th mag. Proper motions of most TGAS stars are improved over their Gaia data and the precision level of TGAS proper motions is extended to many millions more, fainter stars. External comparisons were made using stellar cluster fields and extragalactic sources. The TGAS data allow us to derive the limiting precision of the UCAC x, y data, which is significantly better than 1/100 pixel. Description: The UCAC5 positions on the Gaia coordinate system provide additional data of similar quality to the Hipparcos mission Tycho star observations and thus have the potential to improve the TGAS proper motions. UCAC5 provides new, accurate proper motions for millions of more stars fainter than TGAS, which will allow astronomers to have a preview into research possible only with the next Gaia data release. At the faint end UCAC5 proper motion errors are relatively large due to the low S/N ratio of these observations. Better proper motions for stars fainter than about 15th mag are available from proper motions obtained by combining NOMAD (Cat. I/297/) with Gaia DR1 (Cat. I/337) (catalog of 503 million stars is available upon request), or the recently published PPMXL re-reduction, called the HSOY (Altmann et al., 2017, Cat. I/339) catalog.