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Introduction to the Solar System: Crash Course Astronomy #9 (10:13)

Key Ideas

As this video progresses, key ideas will be introduced to invoke discussion.

Key Ideas

Think about the following questions as you watch the video


  1. 01:59 What kind of model did Copernicus propose for the Universe? One that changed people’s views on Ptolemy’s idea of a geocentric Universe?
  2. 04:07 Why does Phil Plait assert that you can’t define a planet?
  3. 05:34 What facts or trends does Plait claim are giving us hints about how the Solar System was formed?
  4. 06:20 What is angular momentum and how does it work?
  5. 06:50 What are planetesimals and how are they formed?
  6. 08:08 Why did some material form planets and other material did not?