Galactic metallicity is a branch of astronomy that focuses on studying the abundance of chemical elements heavier than hydrogen and helium within galaxies. Metallicity is an important factor in understanding the formation and evolution of galaxies, as well as the processes that drive star formation. By measuring the metallicity of stars within a galaxy, astronomers can learn more about its history, composition, and dynamics. Galactic metallicity research often involves studying the distribution of elements, their ratios, and how they change over time in different regions of a galaxy.