-Luminosity

-The Hertzsprung-Russell Diagram

-Main sequence

-Giant stars

-White dwarf stars

-Nova

-Supernova

-Black hole

-Event horizon

-Singularity

1. Can a star appear to be bright but have low luminosity? Can a star have high luminosity but appear to be dull? Explain how this could be.

2. What are the thee "regions" of the H-R diagram? Briefly describe the relationships between luminosity and temperature for stars in each of the three parts of the diagram.

3. What is the difference between a nova and a supernova? Could a star in the main sequence become a nova? Could a star in the main sequence become a supernova? Why or why not?

4. Briefly describe the formation and "geometry" of a black hole. Could our Sun become a black hole? Why or why not?