DR2 Neighbourhood

Users wishing to look up the E/DR3 record for an astrophysical source identified in DR2 must NOT simply extract the record from E/DR3 having the same source identifier.As described in the detailed description of attribute designation in GaiaSource it is not guaranteed that the same astronomical source will always have the same source identifier in different Data Releases. Hence the only safe way to compare source records between different Data Releases in general is to check the records of proximal source(s) in the same small part of the sky.

This table provides the means to do this via a precomputed crossmatch of such sources, taking into account the proper motions available at E/DR3.Within the neighbourhood of a given E/DR3 source there may be none, one or (rarely) several possible counterparts in DR2 indicated by rows in this table. This occasional source confusion is an inevitable consequence of the merging, splitting and deletion of identifiers introduced in previous releases during the DR3 processing and results in no guaranteed one–to–one correspondence in source identifiers between the releases.For more details of the procedure used to create this crossmatch, see Chapter [chap:archive] in the online documentation.