Study Plan

Learning Goals

By the conclusion of this chapter, you should be able to:
  1. Determine a galaxy’s type from its appearance, and describe the motions of its stars.
  2. Explain how the arms of spiral galaxies form and why they are sites of star formation.
  3. Describe the evidence suggesting that galaxies are composed mostly of dark matter.
  4. Discuss the evidence indicating that most—perhaps all—large galaxies have supermassive black holes at their centers.

Prepare and Assess


    1. Dark Matter
      Section: 20.3
    2. Active Galactic Nuclei
      Section: 20.4

Reassess and Apply

  1. Additional comments or issues to report:

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