Question Sheet: Ringing Saturn


Before reading:

  1. What is especially distinctive about the planet Saturn? Why do you think it would be worth sending a spacecraft to study Saturn and its moons? 
  2. Why are most spacecraft unmanned? What are the advantages and disadvantages of having a person onboard? 
  3. Have you heard or read about any space missions in the news lately? If so, what have you learned? If not, where would you look for information related to space exploration?

During reading:

  1. What is the Cassini spacecraft’s relationship to the Huygens probe? What does each of these vehicles do? 
  2. In what ways is Titan an unusual moon? 
  3. What is methane? 
  4. When was the Cassini mission launched? 
  5. Lunine says, “We’re kind of like glue.” Why does he say that? 
  6. What are the risks of sending an unmanned spacecraft to Saturn? 
  7. How much time will Huygens have to explore Titan if everything goes as planned? Why?

After reading:

  1. Besides photographs, what other data would be important for understanding a planet? 
  2. List the pros and cons of a deep-space mission. 
  3. What does “low density” mean? Explain why Saturn would float in a bathtub filled with water. 
  4. Describe Saturn’s main features. 
  5. What sorts of scientists might be interested in information gathered about Saturn and its moons?


  1. According to NASA, the Cassini-Huygens project is an international collaboration involving three space agencies. Seventeen nations contributed to building the spacecraft. Why did the United States work in collaboration with other countries? 
  2. Who owns space? Describe some dangers or risks of countries claiming pieces of outer space as their own. 
  3. The Cassini spacecraft is named after astronomer Giovanni Domenico Cassini. Who was Cassini and when did he live? See (MacTutor History of Mathematics Archive).


  1. NASA’s Jet Propulsion Laboratory has a special Web site about the Cassini-Huygens mission for kids at Write a review of the site, explaining what you like and don’t like about it. 
  2. Suppose that the Cassini-Huygens mission fails and the spacecraft is destroyed by icy rocks as it passes through Saturn’s rings. Write a news article reporting the failure and describing how various people reacted to the disaster.


The Cassini spacecraft weighs about 5,650 kilograms. Pick an object, weigh it, and figure out how many copies of this object would be necessary to add up to the weight of the spacecraft. Find out how much a school bus weighs. You can find information about school buses at (School Transportation News). Would Cassini be heavier or lighter than a 10-passenger school bus? a 30-passenger school bus?