• Chemical Evolution of the Galaxy

    • The first stars to form in the Galaxy were composed purely of H and He from the Big Bang Right Arrow the Population III stars.

      • These stars evolved producing elements heavier than He.

      • The Population III stars then seeded the Galaxy with these metals through their stellar winds and supernovae.

    • Later (within the first few billion years after the Big Bang), new stars formed with a small percentage of metals Right Arrow the metal-poor, or Population II stars.

    • Over the past 5 billion years, metal enriched stars have been forming out of the material from the evolution of Population II stars Right Arrow the Population I stars. The Sun is an old Population I star.

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