Quiz

1. How do we measure stellar luminosities?
2. How do we measure stellar temperatures?
3. How do we measure stellar masses?
4. What is a Hertzsprung-Russel diagram?
5. What is the significance of the main sequence?
6. What are giants, supergiants, and white dwarfs?
7. What are the two types of star clusters?
8. How do we measure the age of a star cluster?
9. Do we know any cluster older than fourteen billion years?
10. How old is the Universe?