Part A-
1) Why does the photosphere appear to have a sharp edge when the Sun has no solid surface?
2) Why is the Sun's core surrounded by a transparent radiation zone? What role does the more opaque convection zone play in the Sun's interior?
3) What would happen to the Sun if gravity exceeded pressure at some point? What would happen if the pressure exceeded gravity? How does hydrostatic equilibrium regulate the Sun's nuclear fusion rate?
Part B-
1) What is the Main Sequence? How much longer will the Sun remain on the Main Sequence?
2) Jupiter's mass is 10-3 , yet it is often called a "failed star." Explain why this is a very inaccurate description for Jupiter. (Note that true failed stars are called brown dwarfs.)
3) Describe the behavior of the Sun once it leaves the Main Sequence.
Part C-
1) Outline the nebular model for the formation of the Solar System. Include a sketch to illustrate what happens at each stage of the model.
2) List at least 8 observations that support the nebular model of Solar System formation.