4 Jul 2018
Cross-matching Gaia DR2 and GALAH DR2.1
The SkyMapper DR1 catalogue has now been cross-matched against both Gaia DR2 and GALAH DR2.1, with the two tables also being available for TAP queries in the 'ext' schema.
The 1.6 billion Gaia DR2 sources have been cross-matched with SkyMapper DR1, with the results appearing in the gaia_dr2_id1 and gaia_dr2_id2 columns in the dr1.master table, which links the SkyMapper object to the closest and second-closest Gaia DR2 sources, respectively. In addition, the ext.gaia_dr2 table has been augmented with its own gaia_dr2_id1 and gaia_dr2_id2 columns, which are the two closest sources when cross-matching Gaia DR2 against itself.
For the spectroscopic dataset of the GALAH DR2.1 catalogue, the SkyMapper cross-identifications have been placed directly into the ext.spec_galah_dr2p1 table with columns dr1_id and dr1_dist (being the SkyMapper DR1 object_id and the sky distance in arcseconds, respectively).