Tables {AuxIersGdr2CrossId} and {AuxAllwiseAgnGdr2CrossId} list sources whose positions in Gaia DR2 define the celestial reference frame of Gaia DR2 (GaiaCRF2).

{AuxIersGdr2CrossId} lists 2820 sources in Gaia DR2 identified as the optical counterparts of VLBI sources with accurate VLBI positions in the ICRF. The first column is the IERS name of the VLBI source, the second column is the source identifier in Gaia DR2 of the optical counterpart.

{AuxAllwiseAgnGdr2CrossId} lists 555934 sources in Gaia DR2 cross-matched to sources in the AllWISE AGN catalogue . The first column is the AllWISE identifier, the second column is the source identifier in Gaia DR2.

1885 of the Gaia DR2 source identifiers in table {AuxIersGdr2CrossId} appear also in table {AuxAllwiseAgnGdr2CrossId}

The selection of sources is described in . Based on these sources, the quality of the GaiaCRF2 is discussed in .


If you have used Gaia data in your research, please use the following acknowledgement:

This work has made use of data from the European Space Agency (ESA) mission Gaia (, processed by the Gaia Data Processing and Analysis Consortium (DPAC, Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.

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Name Type UCD Unit Description
iers_name char
IERS name
source_id long Gaia source identifier