Table information for 'ucd.data'

General

This table is available for ADQL queries and through the TAP endpoint.

Resource Description: The Unified Content Descriptor (UCD) is a formal vocabulary astronomical data that is controlled by the International Virtual Observatory Alliance (IVOA). The vocabulary is restricted in order to avoid proliferation of terms and synonyms, and controlled in order to avoid ambiguities as far as possible. It is intended to be flexible, so that it is understandable to both humans and computers. UCDs describe astronomical quantities, and they are built by combining words from the controlled vocabulary.

For a list of all services and tables belonging to this table's resource, see Information on resource 'UCD Query'

Further information

The Unified Content Descriptor (UCD) is a formal vocabulary for astronomical data that is controlled by the International Virtual Observatory Alliance (IVOA). The vocabulary is restricted in order to avoid proliferation of terms and synonyms, and controlled in order to avoid ambiguities as far as possible. It is intended to be flexible, so that it is understandable to both humans and computers. UCDs describe astronomical quantities, and they are built by combining words from the controlled vocabulary.

A UCD does not define the units nor the name of a quantity, but rather "what sort of quantity is this?"; for example phys.temperature represents a temperature, without implying a particular unit.

It would be possible to describe astronomical data quantities in a natural language such as English or Hungarian or Uzbek; however, it would be very difficult to expect a machine to 'understand' it in any sense. At the opposite extreme, there is an attempt within the IVOA to describe astronomical data in terms of a hierarchical data model, so that there is a place for everything, and everything is in its place. The UCD vocabulary falls between these extremes, and is intended to be understandable to both humans and computers.

Citing this table

This table has an associated publication. If you use data from it, it may be appropriate to reference 1983MPC..7759...... (ADS BibTeX entry for the publication) either in addition to or instead of the service reference.

To cite the table as such, we suggest the following BibTeX entry:

@MISC{vo:ucd_data,
  year=2013,
  title={{UCD} Query},
  author={Author: Zhang Hailong, {UCD} Center},
  url={http://data.xao.ac.cn/tableinfo/ucd.data},
  howpublished={{VO} resource provided by the {XAO} Data Center}
}

Fields

Sorted by DB column index. [Sort alphabetically]

NameTable Head DescriptionUnitUCD
ucd UCD Unified Content Descriptors from IVOA N/A N/A
ucd_desc Description. The simple explaination of UCD N/A N/A

Columns that are parts of indices are marked like this.

Other

The following services may use the data contained in this table:

VOResource

VO nerds may sometimes need VOResource XML for this table.

More Information on the Base Resource

The Unified Content Descriptor (UCD) is a formal vocabulary for astronomical data that is controlled by the International Virtual Observatory Alliance (IVOA). The vocabulary is restricted in order to avoid proliferation of terms and synonyms, and controlled in order to avoid ambiguities as far as possible. It is intended to be flexible, so that it is understandable to both humans and computers. UCDs describe astronomical quantities, and they are built by combining words from the controlled vocabulary.

A UCD does not define the units nor the name of a quantity, but rather "what sort of quantity is this?"; for example phys.temperature represents a temperature, without implying a particular unit.

It would be possible to describe astronomical data quantities in a natural language such as English or Hungarian or Uzbek; however, it would be very difficult to expect a machine to 'understand' it in any sense. At the opposite extreme, there is an attempt within the IVOA to describe astronomical data in terms of a hierarchical data model, so that there is a place for everything, and everything is in its place. The UCD vocabulary falls between these extremes, and is intended to be understandable to both humans and computers.

Copyright and such: The data List of UCD obtained from ucd1p-words-20070402.txt (http://cdsweb.u-strasbg.fr/UCD/).