1. Main Sequence: This is the longest stage of a star's life, where it fuses hydrogen into helium in its core. Our Sun is currently in this stage.
2. Red Giant: As the star runs out of hydrogen fuel in its core, it expands and cools, becoming a red giant. The outer layers swell, and the star's surface temperature decreases.
3. Horizontal Branch: This stage is less obvious and only occurs for a short time. The star fuses helium in its core, and the outer layers contract while the core expands.
4. Asymptotic Giant Branch (AGB): This is the final stage before the star sheds its outer layers. The star experiences further expansion and cooling, becoming even redder.
5. Planetary Nebula: As the AGB star reaches the end of its life, it expels its outer layers, forming a beautiful, expanding cloud of gas and dust called a planetary nebula. The core of the star remains behind, now a hot, dense white dwarf.
6. White Dwarf: This is the final stage for stars like the Sun. The white dwarf is the dense, hot core of the original star that slowly cools over billions of years. It is supported by electron degeneracy pressure, preventing it from collapsing further.
Note: The final fate of a star with a mass similar to the Sun is to become a white dwarf. There is no further evolution beyond this stage.
It is important to note that this is a general overview of the stages for stars with masses similar to the Sun. The details can vary slightly depending on the star's initial mass and composition.
