Question Sheet: Strange Universe: The Stuff of Darkness


Before reading:

  1. What is matter? 
  2. What do you think might lie hidden in the darkness between stars? 
  3. Name three things studied by scientists that your eye can’t see directly.

During reading:

  1. What is the difference between ordinary matter and dark matter? 
  2. Explain why the force of gravity of the sun is greater than the force of gravity of a car. 
  3. If dark matter can’t be seen, how do we know that it might exist? 
  4. What problem did scientists discover with the Big Bang theory? 
  5. Explain the difference between dark matter and dark energy. 
  6. What does astronomer Robert Kirshner mean when he says, “We’re just now beginning to peel away the darkness”?

After reading:

  1. If you were interested in learning more about dark matter or dark energy, where would you look? Name three resources for further inquiry. 
  2. Why do scientists think the universe is expanding? 
  3. Dark matter is still very mysterious stuff. Describe some of the candidates for what dark matter might be.


  1. Imagine that you are a bug living under a rock. Describe what the “universe” might look like to you. 
  2. Do you think we could understand a universe outside our own? Why or why not? 
  3. If you were an astronomer and wanted to study dark matter or dark energy, you might apply for a grant to help pay for the investigation. Write a persuasive paragraph explaining why such a study would be worthwhile.


Earth has a mass of about 6 million billion billion kilograms, and the sun has a mass of about 2,000 billion billion billion kilograms. Express each of these two numbers as a power of 10. The sun is how many times more massive than Earth?