A Binary-Star Revolution in the Gaia Era

Binary and multiple stars are fundamental to how stars form, evolve, and sometimes explode, yet for decades, we only saw the tip of the iceberg. Gaia is now revealing the full structure below the surface. In my talk, I will show how Gaia revolutionised the field by detecting hundreds of thousands of these hidden companions. I will give an overview of key discoveries from the DR3 Non-Single Star catalogue, including how stellar tides reshape orbits, how Gaia is uncovering candidates for dormant black holes, and what close-binary fractions in halo stars and globular clusters tell us about the early Milky Way. I will then explore Gaia’s ability to map multiple star systems of hierarchical triples and quadruples, offering new clues about star formation and long-term dynamical evolution. I will finish with a look ahead to Gaia DR4 and how it will open a new window onto the binary architecture of our Galaxy.

Note:
Dolev is a candidate for a faculty position in the department.