1. Why are numerous impact craters found on Ganymede and Callisto but not on Io or Europa? 2. Describe the structure of Saturn’s rings. What are they made of? 3. To test your knowledge of Saturn’s...

1. Why are numerous impact craters found on Ganymede and Callisto but not on Io or Europa?

2. Describe the structure of Saturn’s rings. What are they made of?

3. To test your knowledge of Saturn’s rings, do Interactive Exercise 8-4 on the Web. You can print out your results, if required.