Galaxies and the Universe

Learning Goal #17: I can ask thoughtful questions about galaxies and our universe.

Guiding Questions:

  1. What is a galaxy?
  2. What are the main shapes of galaxies?
  3. What is a black hole?
  4. Why do we know so little about black holes?
  5. What is dark matter?
  6. What is Earth’s place in the universe?

What is a galaxy?

  • A galaxy is an arrangement of billions of stars, dust, and gas, bound together by gravity.
  • Many galaxies have a central area of older stars, with newer stars spreading around the outside
  • Brainpop: Galaxies
  • NASA Space Place: What is a galaxy?

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What are the main shapes of galaxies?

  • There are a few different ways to classify galaxies, but most astronomers agree that there are three main types:
    • Spiral
      • Oridnary
      • Barred-Spiral
    • Elliptical
      • Lenticular
    • Irregular
      • Clouds
  • Tutorial: Classification of Galaxies 

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What is a black hole, and why do we know so little about them?

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What is dark matter?


 

What is Earth’s place in the universe?

Toggle through the slideshow below to identify “Earth’s Place” in the universe.

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