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Star Life Cycle

Page 1: Star Life Cycle, What’s out in Space?

  1. How is a star’s life cycle like a human’s life cycle?
  1. What is a nebula? Why are they important to a star’s life cycle?

Page 2: Protostars and the Nebula

  1. Watch the animation of how a star begins to form out of a nebula. What is a protostar?
  1. What causes the dust and gas to clump together and eventually turn into a protostar?
  1. What nuclear process occurs that marks the official “birth” of the star?

Page 3: Stars

  1. What is a star?
  1. Stars spend most of their lives as a main sequence star. What is a main sequence star?
  1. Complete the interactive lab. Click through the animations for each possible starting mass of a star. How does the starting mass of a star affect how long it is on the main sequence? (In other words, does a more massive star have a longer or shorter life on the main sequence?)

Page 4: Stars, Equilibrium, Hydrogen burning (fusion)

  1. What is equilibrium and why does a star want to reach equilibrium?
  1. Read through the rest of the info on this page.
  1. Test your knowledge with the Star Quiz (part 1) at the bottom of the page.

Page 5: Stars: The beginning of the end

  1. Read through the info on this page.
  1. Test your knowledge with the Star Quiz (part 2).
  1. What happens after the hydrogen burns out and the star begins to burn helium? What is the next stage of a star after main sequence?

Page 6: Stars: The End of a Star

  1. What happens to a low-mass star after it is a red giant? What stage is next?
  1. For medium-mass stars, what type of star does this become after the red giant stage?
  1. What is a supernova?
  1. What could happen to the largest mass stars? What could they become?
  1. Complete the interactive lab at the bottom of the page to see how different sized stars have different life cycles.

Page 7: Hertzsprung-Russell Diagram

  1. What two variables are graphed on an H-R diagram?
  1. What is the absolute magnitude of a star?
  1. Complete the interactive lab of the H-R diagram on this page.
  2. What are the two characteristics (temp and brightness) of a red giant in the upper-right corner of the graph?
  1. What are the two characteristics (temp and brightness) of a main sequence star in the middle of the graph?
  1. What are the two characteristics (temp and brightness) of a white-dwarf in the lower-left corner of the graph?

Page 8: Applications of the HR Diagram

  1. Complete the interactive lab.

Page 9: Interactive H-R Diagrams

  1. Complete the Interactive Lab.
  1. Complete “More HR Diagram Fun” activity & questions.