The first stars formed from the primordial gas of just hydrogen and helium left behind after the Big Bang. Later generations of stars formed from gas enriched in metals that were previously forged in the cores of the first stars. This process of element production and enrichment of the surrounding gas is called the chemical evolution. Among the second and later generations of stars were low mass stars with long lifetimes that make them still observable today. This allows astronomers to study how elements were created over cosmic time.
Associated Book Chapters from Searching for the Oldest Stars: Ancient Relics from the Early Universe
- Chapter 3: Stars, Stars, More Stars
- Chapter 4: Stellar Evolution—From Birth to Death
- Chapter 9: The Chemical Evolution of the Early Universe