Population II stars

Population II stars are ancient stars formed early in the universe's history, containing very little of the heavier elements (like carbon, oxygen, and iron) that planets and newer stars have. They tend to be older, cooler, and often found in the dense centers of galaxies and globular clusters. Because they formed when the universe had fewer heavy elements, their composition offers clues about the early conditions of the cosmos and the process of stellar evolution over billions of years.