Winding, Unwinding and Rewinding the Gaia Phase Spiral

The discovery of the Gaia phase spiral has transformed our understanding of the Milky Way’s dynamics, revealing that the Galactic disc is far from equilibrium. This complex phase space structure encodes valuable information about past perturbations experienced by the Milky Way, its mass distribution, and ongoing dynamical processes. Six years after its discovery, this workshop provides a platform to assess recent progress and explore future directions in this rapidly evolving field.

The workshop aims to bring together experts in observational astronomy, numerical simulations, and theoretical modeling to tackle key questions about the origin, evolution, and implications of the phase spiral. Specific topics include:

• Overcoming limitations in simulations and analytical models.
• Exploring new observational prospects to test theoretical predictions.
• Identifying the most likely scenarios for the phase spiral’s formation.
• Understanding the broader lessons the phase spiral offers about the Milky Way’s evolution.

The program includes a combination of collaborative keynote talks, talks by young researchers, group work sessions, and discussions, designed to foster interdisciplinary exchange and collaboration. A key outcome of the workshop will be a roadmap identifying promising directions for future research.

The Gaia phase spiral stands as one of the most fascinating yet complex discoveries of the Gaia mission. This workshop aims to accelerate progress in unraveling its nature and implications for galactic dynamics by fostering the in-depth exploration and collaboration essential to tackling this grand challenge.