Chapters 12-15 in your text (Seeds Horizons: Exploring the Universe) corresponding to Lessons 14-18 (videotape series) - see review for Exam II from orientation materials and Study Guide for video telecourse. The videos supplement and demonstrate examples and specific ideas from the material presented in the text.

Things to note -

1. words in bold type
2. Summary and New Terms at the end of each chapter
3. Review questions at the end of each chapter
4. Problems at the end of each chapter

Chapter 12 - The Milky Way Galaxy

1. Variable stars - instability strip (see Fig 12-2) - RR Lyrae variables, Type I & Type II Cepheid variables, Henrietta Leavitt and the period-luminosity relation
2. Harlow Shapley - distances to globular clusters - see Window on Science 12-1
3. Components of our galaxy
4. Neutral hydrogen 21 cm radiation - see Fig 12-7
5. Mass of the Milky Way Galaxy - differential rotation - what happens to spiral arms?
6. How do we estimate the age of the Milky Way galaxy?
7. Population I and Population II stars - what differences?
8. How did our galaxy form?
9. Spiral Arms and Star Formation - What are spiral arm tracers? What spiral arms have been mapped? What has been used to map the spiral arms? Look at the figures!! What is a density wave?
10. What is Sagittarius A? Black Hole in the center of the Milky Way?

1. How are galaxies classified? Why? Hubble's Tuning Fork diagram (Fig 13-2) How are distances determined? (see Fig 13-9)
2. What are H II regions? How are different properties (diameter, luminosity, mass, …) of galaxies determined?
3. Hubble's Law, Hubble's constant, …
4. What is dark matter? Why is it an important issue? What's a WIMP?
5. How do we determine how galaxies evolve? What do we really observe in studying clusters of galaxies?
6. What is galactic canabalism?

1. When is a galaxy classified as 'active'? What clues?
2. What different classes of these objects?
3. STUDY Unified Model of Active Galactic Nuclei
4. What is a Quasar? Model for Quasar, distances to Quasars, …
5. Red shift - what is the difference between two formulas?

1. Know Olbers' paradox, what it means, etc
2. What is assumed about how smooth-ness or homogeneity of the early universe?
3. Cosmological principle - curvature of space-time, …
4. Big Bang - primordial background radiation,
5. Why was there a matter-antimatter asymmetry?
6. What was the universe like at different times as it cooled?
7. Observations and theory - Why is Hubble Time an overestimate of the age of the universe?
8. Origin of structure…
9. How many galaxy seeds do you have to plant (and where and when) before you grow a galaxy?