1. Have you thoroughly read chapter 12?

2. Briefly explain the importance of the Rosetta stone.

3. How many spacecraft have we launched so far that gone past the orbit of Pluto and will travel to the stars?

4. List the factors in the Drake equation.

5. Which of the factors in the Drake equation is hardest to estimate?

6. Does Sagan feel an interstellar radio communication would be easy or difficult to decode?

7. What do we and "they" [ETs] have in common as a language?

8. Where is the largest single-dish radio telescope on Earth? (hint: watch "Contact")

9. How does Sagan feel about stories of extra-terrestrial visitations to Earth?

10. List a couple of things in the Arecibo Interstellar Message (see page 290).