After placing the Gaia mission in the context of current astrophysical research, the astrometric, photometric, and spectroscopic data provided by the satellite, as presented in its third data archive, DR3, will be reviewed. Gaia third archive contains, in addition to the measurements from the satellite's instruments, an extensive set of astrophysical parameters derived by the DPAC data processing consortium, for stars, unresolved galaxies, and solar system objects. These parameters correspond to about 1.8 billion sources repeatedly observed by the satellite during the first 34 months of operation. In the case of the Milky Way stars, DR3 contains information for about 1% of its stars, which has made it possible, for the first time, to study the dynamics of the disk and the halo, and to reconstruct the tumultuous evolutionary history of our galaxy, which is etched in its halo. Studying the integrals of the motion and the orbital actions, some 15 episodes of accretion of other galaxies by our galaxy have been identified, which shows that our Galaxy is the result of billions of years of "galactic canibalism". Accretion phenomena and tidal current trails are frequently observed in other galaxies and show that our Universe evolves through a hierarchical formation of galaxies.
Meeting will be held online
Meeting ID: 874 5529 5473