Gaia EDR3 known issues - Gaia
Known issues with the Gaia EDR3 data
This page lists any issues found in Gaia Early Data Release 3 which could not be incorporated into the official data release, or which were discovered after the release of the data and publication of the release documentation. The Gaia EDR3 contents page contains a summary of limitations that are known, and documented, at the release. Further information can be found from the data release documentation, as well as from the data release processing papers.
Sections 6.3.2, 7.2, and Appendix A in the Gaia EDR3 release paper erroneously state that the correction to the G-band fluxes and magnitudes presented in Riello et al. (2021) (their Table 5) should be applied to sources in Gaia EDR3 with six-parameter astrometric solutions. In fact, the corrections should be applied to sources with two-parameter or six-parameter astrometric solutions. The corrected ADQL query and Python source code are presented in a corrigendum to the paper. The Python code has also been corrected on Github .
Following the discovery of the above error, a more detailed investigation was done for the sources with two-parameter (2-p) astrometric solutions. Out of the 344 million 2-p sources present in Gaia EDR3, about 20 million have an astrometric solution in which the actual source colour was used instead of a default colour. This means that for these 20 million 2-p sources the G-band correction should actually not be applied. These sources are mostly faint, with 96% at magnitudes G>20, and for 75% of these 20 million sources the correction that is (wrongly) applied amounts to less than ~4 milli-magnitudes. It was thus decided not to make a special effort to exclude these sources from the correction.
Should a user of the Gaia EDR3 data wish to undo the wrong correction for one or more of these 20 million sources, the list of source IDs and applied corrections can be provided on request.
NOTE: the corrections to the G-band photometry are planned to be included in Gaia DR3.