Name ______Date ______Per. ______

Unit 7 Review Worksheet

  1. Draw a diagram illustrating the structure of the sun. Label each layer.
  1. Discuss how the sun produces energy in the core and describe how the sun remains in gravitational equilibrium.
  1. Describe the transport of energy, from the deep interior of the sun, to when it finally reaches the Earth. Include the various methods of transport.*
  2. Discuss the nature of the Sun’s magnetic field and its relationship to the various types of solar activity.
  1. Describe the appearance of the photosphere and the “structure” of a sunspot.
  1. Describe the sunspot cycle.
  1. Describe how a star forms from an interstellar cloud. Include a description of each stage ending with when the star enters the main sequence.
  1. Briefly explain why high-mass stars have shorter lifetimes than low-mass stars. What are the lower end cutoff and upper limit on the mass of a star?*
  1. Explain why stars evolve off the main sequence.
  2. Summarize or illustrate the evolutionary stages followed by a Sun-like star once it leaves the main sequence.
  1. Describe the properties of a white dwarf and explain what supports it. Include the upper mass limit for this type of star.
  2. Explain how white dwarfs in binary systems can become explosively active.
  1. Describe or illustrate the evolutionary stages of high-mass stars once they leave the main sequence. Include a description of how the star generates energy in the core and which process finally dooms it.
  2. Explain how neutron stars are formed. Include a description of how heavy elements are made during the explosion.
  1. Describe the properties of neutron stars. Include a discussion of what supports the star and what the upper mass limit for neutron stars is.
  2. Describe what happens to stars with a mass too big to be a neutron star. What is the name of the spherical surface of space that defines this object? Why can’t we see them?
  3. Describe the difference between a nova and a supernova.
  1. Explain how stellar distances are determined using parallax. How far out can this technique be applied? How many stars can be measured with this technique?*
  1. So if a star has a parallax angle of 0.5 arcseconds, its distance would be two parsecs.
  1. Distinguish between luminosity and apparent brightness, and explain how stellar luminosity is determined.
  1. Distinguish between apparent magnitude and absolute magnitude. What factors affect the apparent magnitude?
  1. Explain the usefulness of classifying stars according to their colors, surface temperatures, and spectral characteristics. What is OBAFGKM?
  1. Describe how a Hertzsprung–Russell diagram is constructed and used to identify stellar properties.
  1. Explain how the age of a star cluster can be determined using the HR diagram.