Princeton University Thunch Talk

Mass is the most fundamental stellar parameter of stars. The mass of a star largely determines its stellar structure, surface temperature, luminosity, chemical evolution, lifetime, and its ultimate fate. However, robust stellar mass measurements are challenging since we cannot place a star on a weight scale. In this talk, I will demonstrate how we can use the wide binary stars from Gaia to measure the dynamical masses for (nearly) all the stars across the Hertzsprung-Russell diagram (https://arxiv.org/abs/2308.08584). The mass measurements are solely based on Newtonian dynamics, without assumptions from stellar models. I will discuss the implications for single-star isochrones, compact binary and triple populations, special populations like white dwarfs and pre-main-sequence stars, and the prospect of constraining the occurrence rate of compact objects and testing gravity (e.g. MOND).