Life Cycle Stages
Each stage of a star’s life involves some process within the star (fusion in its core, fusion in a shell, electron degeneracy, etc.) trying to prevent gravity from crushing the star into a singularity. Below is a diagram showing six stages in the life of a star with a mass identical to our Sun.
Figure 2. The stages that a one-solar-mass star will go through during its life cycle plotted on an HR diagram
For each stage shown in the figure above, explain what is happening to the nebula or star (shrinking, growing, fusion, etc.) and what is happening to offset the force of gravity. W r i t e a few sentences for each stage.
• Stage 1: Nebula
• Stage 2: Protostar
• Stage 3: Main Sequence
• Stage 4: Red Giant
• Stage 5: Planetary Nebula/AGB
• Stage 6: White Dwarf