21. The Initial Gaia Source List (IGSL) ID: ivo://CDS.VizieR/I/324 Title: The Initial Gaia Source List (IGSL) Short Name: I/324 Date: 21 Oct 2021 Publisher: CDS Description: The Initial Gaia Source List will be the starting point for the Gaia Initial Data Treatment. The Attitude Star Catalog will be used by the first iteration of the on-ground attitude reconstruction.