Learning about Galactic structure with Gaia astrometry

TL;DR

This paper discusses how Gaia astrometry can be used to develop a comprehensive dynamical model of the Milky Way by comparing predicted and actual catalogue data, emphasizing the importance of calibration and complementary data.

Contribution

It proposes a framework for building a dynamical model of the galaxy using Gaia data and highlights the need for calibration and supplementary surveys.

Findings

Gaia will provide extensive astrometric data for Galactic studies.

Calibration of photometric distances is essential for faint stars.

Combining Gaia with other surveys enhances Galactic modeling.

Abstract

The Gaia mission is reviewed together with the expected contents of the final catalogue. It is then argued that the ultimate goal of Galactic structure studies with Gaia astrometry should be to build a dynamical model of our galaxy which is capable of explaining the contents of the Gaia catalogue. This will be possible only by comparing predicted catalogue data to Gaia's actual measurements. To complement this approach the Gaia catalogue should be used to recalibrate photometric distance and abundance indicators across the HR-diagram in order to overcome the lack of precise parallax data at the faint end of the astrometric survey. Using complementary photometric and spectroscopic data from other surveys will be essential in this respect.