standards > terminology artifact > DOI:10.25504/FAIRsharing.ochiOn

ready IVOA Standard for Unified Content Descriptors

Abbreviation: IVOA UCD

General Information
The IVOA Standard for Unified Content Descriptors document describes the current understanding of the IVOA controlled vocabulary for describing astronomical data quantities, called Unified Content Descriptors (UCDs). The present document defines a new standard (named UCD1+) improving the first generation of UCDs (UCD1). The basic idea is to adopt a new syntax and vocabulary requiring little effort for people to adapt software already using UCD1. This document also addresses the questions of maintenance and evolution of the UCD1+. Examples of use cases within the Virtual Observatory and tools for using UCD1+ are also described.


Countries that developed this resource Worldwide

Created in 2005

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How to cite this record IVOA UCD; IVOA Standard for Unified Content Descriptors; DOI:; Last edited: Jan. 8, 2019, 1:27 p.m.; Last accessed: Nov 20 2019 11:14 p.m.

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Record added: May 1, 2018, 11:30 a.m.
Record updated: Oct. 5, 2018, 8:35 a.m. by carviset.

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Implementing Databases (1)
VizieR astronomical catalogue database
VizieR is a 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. To be deposited within VizieR, data must be related to a publication in a refereed journal, either as tables or catalogues actually published, or as a paper describing the data and their context. VizieR is certified by the CoreTrustSeal. DOI: 10.26093/cds/vizier

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