VizieR provides the most complete library of published astronomical catalogues --tables and associated data-- with verified and enriched data, accessible via multiple interfaces.
Query tools allow the user to select relevant data tables and to extract and format records matching given criteria. Currently, 24813 catalogues are available
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VizieR was initially started as a joint effort of CDS (Centre de Données astronomiques de Strasbourg)
and ESA-ESRIN (Information Systems Division), and is now fully managed by CDS.
VizieR has been available since 1996, and was described in a paper published in A&AS 143, 23 (2000).
Note that VizieR does not contain all available online catalogues; some catalogues are not suitable and some less frequently used catalogues have not yet been incorporated into the VizieR database. These last ones can be accessed by FTP from the Astronomer's Bazaar.