ASTR 220 STUDY QUESTIONS for GALAXIES Hamilton Spring 98 The final exam will be worth 125 pts. The format will be similar to the previous exams. 50 Multiple Choice & True False (1 1/2 pts. each) 75 points 5 Short Answer Questions 50 points ----------------------------------------------------------------- Total 125 points The final will be cumulative covering material from the entire course. The material since Exam II, however, will be more heavily weighted. Approximately 40% of the multiple choice questions and at least three of the short answer questions will be on this material. Use the previous two review sheets, quizzes, Exam I, Exam II, homeworks, both books, handouts, and notes to study. There is a lot of material, so start studying early! 1. How did Henrietta Leavitt calibrate the Period/Luminosity relation for Cepheid variables? 2. How did Hubble demonstrate that the Andromeda spiral nebula lies beyond the Milky Way? 3. What is Hubble's Law? How is it used by astronomers today? 4. Compare the appearance and causes for thermal and non-thermal emission in galaxies. 5. How does the history of radio astronomy demonstrate the link between progress in technology and new scientific discoveries? 6. Describe the observations of the two basic structures seen for radio galaxies. 7. How is synchrotron radiation produced? 8. What is the Local Group? Why do astronomers believe most galaxies are members of clusters? 9. What new techniques have improved the resolution of radio telescopes? 10. What type of stars do we see in spiral arms? In a spiral galaxy's nuclear bulge? In an Elliptical Galaxy? In globular clusters? How do the type of stars present in these areas depend on the amount of dust and gas present between stars? 11. Black holes with a few solar masses are created in supernova explosions. Where are super massive (million and billion solar mass) black holes believed to come from? 12. Describe the observations made of quasars. 13. How do astronomers account for the observations made of quasars using the SMBH model? 14. How can "angle of observation" affect the observations made of active galaxies? 16. Describe how a double image, arc, ring or quadruple image can be produced by a gravitational lens. 17. Is there a black hole at the Milky Way's core? Discuss observations and theory. 18. Why are infrared and radio emissions used to study the Milky Way's core? 19. Why is Centaurus A a good candidate for two galaxies in collision? 20. Be able to compare the separation between galaxies to the separation between stars. What does this calculation imply about the frequency of collisions? 21. Why are computer simulations of interacting galaxies useful? What do they show? 22. What types of structures are observed when two galaxies move past one another? move through one another? merge? 23. How are globular star clusters used to estimate age of the Milky Way? 24. What changes can occur as a galaxy evolves (changes over time)? How does an "evolving" model help explain the observations of quasars and AGNs? What effect do colliding galaxies have on this model? 25. How are the galaxies arranged in space? (Bubbles & Voids model) 26. What is dark matter? What role might it play in collisions? 27. How did the universe begin? What are the theories for its future? You should be familiar with the following terms, people, and objects. Many of them can be found in the index of our book "Colliding Galaxies". Harlow Shapley Alar and Juri Toomre Antennae Galaxy John Herschel Cepheid Variables Period/Luminosity Relation Karl Jansky Hubble's Constant Gravitational Lens Charles Messier Einstein's Cross Super Massive Black Hole Model Edwin Hubble Centaurus A Streamers Henrietta Leavitt Cygnus A Bridges Elliptical Galaxy Binary Galaxy Globular Cluster Spiral Galaxy Radio Jets & Lobes Merging Galaxies Irregular Galaxy Polar Ring Galaxy Active Galactic Nuclei (AGNs) Barred Spiral Galaxy Quasars Coma Cluster VLA Accretion Disk Virgo Cluster VLBI Orientation Model Population I & II Stars Interferometry Double Nucleus Big Bang Local Group Magellenic Clouds Magellenic Stream Superclusters Active Galaxy N Galaxy Seyfert Galaxy Redshift Nuclear Bulge Whirlpool Galaxy (M51) Great Wall Great Attractor Sagittarius A Andromeda Galaxy (M31) Starburst Galaxies Big Crunch Bubbles & Voids Ever Expanding Palomar National Geographic Sky Survey Dark Matter Final exam: Saturday May 16 from 8:00-10:00 AM in CSS 2400. Last Day of Class: Wednesday May 13. Review Session: A few days before the Final in CSS 2400. The exact time will be posted on the class web page. Extra Office Hours: All afternoon Thursday and Friday before the Final in CSS 1245. Good luck on your Finals and I hope that you enjoyed this class!