1. Chapter 8: Moons, Rings and Pluto Titan is Saturn's largest moon and is very similar to Ganymede and Callisto in mass, radius, and density. This implies that Titan may have a rocky core with a thick mantel of ice also. Titan can retain a thick atmosphere made up of Nitrogen, argon and methane because it is so cool.

2. Chapter 8: Moons, Rings and Pluto Triton is Neptune’s largest moon. It is very cold (37ko) and has a thin atmosphere of nitrogen and an icy surface that reflects a lot of sunlight. The nitrogen condenses and can be seen as frost near the south pole of the moon. Voyager II also saw great jets of nitrogen erupting from its surface. Triton has a retrograde orbit around Neptune.

3. Chapter 8: Moons, Rings and Pluto Medium sized moons of Saturn

4. Chapter 8: Moons, Rings and Pluto Five medium sized moons of Uranus

5. Chapter 8: Moons, Rings and Pluto Miranda is an asteroid sized moon of Uranus with an odd fractured, grooved surface which is currently unexplained.

6. Chapter 8: Moons, Rings and Pluto Saturn’s Rings Rings are made up of small rocks and dust and not a solid sheet of material. The rings composed of thousands of smaller ringlets which are caused by gravitational resonances produced by the many moons.

7. Chapter 8: Moons, Rings and Pluto False color image of Saturn’s rings as seen form Voyager II compared to size of the Earth. The rings are shepherded by moons that can twist the ringlets into thin ribbons.

8. Chapter 8: Moons, Rings and Pluto Astronomers think rings are produced when moons get too close to a planet and gravitational tidal forces break them apart. The distance where they break apart is called the Roche limit.

9. Chapter 8: Moons, Rings and Pluto Rings of other planets

10. Chapter 8: Moons, Rings and Pluto Astronomers can use occultations to see how starlight changes when the rings pass in front. How Uranus’ rings were discovered

11. Chapter 8: Moons, Rings and Pluto Uranus’ rings as seen by Voyager II Shepherd moons of the epsilon ring

12. Chapter 8: Moons, Rings and Pluto Neptune’s Rings

13. Chapter 8: Moons, Rings and Pluto Ground based discovery photo of Pluto’s moon Charon Hubble Space Telescope image of Pluto and its moon. Both Pluto and its moon are tidally locked to each other.

14. Chapter 8: Moons, Rings and Pluto Pluto - Charon system