1. Have you thoroughly read chapter 10?

2. Think of a way for inhabitants of Flatland to distinguish between circles and squares without touching them.

3. Sagan says the total amount of energy from outside the solar system ever received by all the radio telescopes on the planet Earth is less than what?

4. About how many times has the sun orbited around the center of the Milky Way?

5. What did Hubble discover about the relation between the distance to a galaxy and its Doppler shift?

6. How was Humason able to photograph galaxies that he couldn't see through the telescope?

7. Are quasars near or far?

8. How do we know the answer to #7?

9. Are most galaxies redshifted or blueshifted?

10. Where is the Very Large Array?