What is the probability that an astronomical object of certain properties enters the Gaia catalogue (or not)? The GaiaUnlimited project aims to enable the full potential of Gaia by characterising its survey selection function, as well as for different subsamples of the data, which are key ingredients in most statistical studies of the Milky Way. By comparing Gaia with deeper imaging from the...
Despite its discovery almost 30 years ago and its subsequent mapping of its core and tidal tails, the progenitor mass of Sagittarius is still highly uncertain/debated, spanning almost two orders of magnitudes!
On the one hand, recent observations of the chemo-dynamical structure of Sgr's stellar stream and structure of the outer disc favour a massive progenitor with $>6\times10^{10}\,...
The Large Magellanic Cloud (LMC) turns out to be a unique and impressive test laboratory thanks to the latest Gaia Data Release 3. Being the closest galaxy in the Local Group, Gaia proper motions and line-of-sight velocities allow it to make 3D velocity maps for the first time (Jiménez-Arranz+23) and endeavour dynamical studies in detail, such as the determination of the LMC bar pattern speed...
Gaia Data Release 2 revealed that the Milky Way contains significant indications of departures from equilibrium in the form of asymmetric features in the phase space density of stars in the Solar neighbourhood. One such feature is the z-vz phase spiral, interpreted as the response of the disc to the influence of a perturbation perpendicular to the disc plane, which could be external (e.g. a...
Radial abundance gradients in the Galactic disc are one of the most important observational constraints to study the chemical evolution of the Milky Way galaxy and also other galaxies in the universe. The radial gradient is the result of many physical processes that occur since the formation of the Galaxy, as e.g. the infalling gas to form the disc, the star formation history, radial gas...
We map chemical inhomogeneities in the Milky Way’s disc out to a distance of ~4 kpc from the Sun, using different samples of bright giant stars in Gaia Data Release 3. The samples are selected using effective temperatures and surface gravities from the GSP-Spec module, and they are expected to trace stellar populations of a different typical age. The cool (old) giants exhibit a relatively...
Our understanding of the Milky Way’s formation history can be refined by analyzing the information encoded in its oldest stellar populations, typically their chemical composition and orbital motion. Having access to such properties is valuable to depict a larger picture of the earliest stages of galactic formation. With the rise of Gaia, an orbital characterization of the different components...
