The ESA Gaia space mission is a major project for the European astronomical community, which is deeply changing our view of the Galaxy with a precise and detailed stereoscopic survey of around 1.8 billion celestial objects down to 20 mag. Gaia represents a huge leap forward with respect to ESA’s Hipparcos satellite for astrometry: the Gaia satellite is performing micro-arcsecond global astrometry, two orders of magnitude more accurate than Hipparcos.
This very high-accuracy astrometry allows Gaia to measure the 3D position of a star and its movement projected on the celestial sphere. Gaia is also gathering spectroscopic data, allowing the determination of the radial velocities and, combined with proper motions, of the true space velocities for several millions of galactic stars. In addition, Gaia spectro-photometric data allow measuring the astrophysical properties, including luminosity, surface gravity, temperature and chemical composition.
So far, four Gaia catalogues have been released: Gaia DR1 on September 14th, 2016, Gaia DR2 on April 25th, 2018, Gaia Early DR3 on December 3rd, 2020 and Gaia DR3 on June 13th, 2022. The fourth data release is foreseen not before the end of 2026, while the final release with the complete Gaia Legacy Archive of all data is planned in 2030.
Fig. 1: The GaiaPortal at SSDC
In the framework of a wide international collaboration, the Space Science Data Center (SSDC) contributes to DPAC-CU9, the coordination unit that is responsible for the realization of the Catalogue and the release of the Gaia data. On behalf of CU9, the Gaia Team at SSDC is in charge of the cross-match of the Gaia catalogue with the largest public available optical and near-IR catalogues [Marrese et al. 2017, 2019].
SSDC is one of the five ESA partner data centers for the publication and dissemination of Gaia data releases. SSDC has thus designed, developed, and made publicly available a point of access to the Gaia and cross-matched external catalogues data: the GaiaPortal. SSDC is continuing to develop access, data extraction and multi-wavelength cross-match tools to enable the astronomical community to handle and fully exploit the scientific potential of this enormous archive.
SSDC is also deeply involved in DPAC-CU5, the coordination unit responsible for the analysis of the Gaia spectro-photometric data. SSDC is building the archive and database of the ancillary data produced by the CU5 Italian teams involved in Gaia. Ancillary data constitute the collection of all the measurements, observations and simulations required for the reduction and absolute calibration of the Gaia spectro-photometric observations (SPSS@SSDC). SSDC Gaia team is involved in all aspects of the data reduction and analysis [Altavilla et al. 2021] aimed at building the Gaia Spectro-Photometric Standard Stars grid.
Main projecs:
- ESA Gaia
People involved: P.M. Marrese, S. Marinoni, M. Fabrizio, G. Altavilla
Publications and Meetings:
- Marrese et al. 2017, A&A, 607, 105
- Marrese et al. 2019, A&A, 621, 144
- Altavilla et al. 2021, MNRAS, 501, 284