Complete Table 21.1 comparing two stages and indicating whether the temperature, luminosity, and radius each increased, decreased, or stayed the same. We have shown an example for the changes from Stage A to Stage B. The changes that you list in Table 21.1 are observable changes that astronomers might detect if they watched the Sun evolve from afar. These observable changes are caused by changes in the amount, location, and type of fusion that is happening within the star.
Combine all of the information from the background Figure 21.1 and Table 21.1 and fill in Table 21.2 as follows:
For columns 2-5, determine from Figure 21.1 when fusion is occurring in the core or in the shell, or both and the kind of fusion process taking place.
For column 6, check when electron degeneracy is present in the core.
For column 7-9, indicate what is supporting the rest of the star. If the star is in equilibrium, then pressure and gravity are in balance. Put a check in column 8 if the rest of the star is contracting( gravity > pressure). Put a check in column 9 if the rest of the star is expanding(pressure> gravity).
- Stage F: a. What happens to the rest of the star when stage F on the H-R diagram is reached?
b. What is the object called, and what is the fate of the material?
- Stage F and before "The End" on the H-R diagram, Stage G is reached by the Sun.
Stage G: a. What is this object called?
b. Compare the size of the Sun relative to what it was when on the main sequence.
Sample Solution