1.HINTS ON TAKING "OPEN BOOK AND NOTES" TESTS:
a. Study as if it were a closed book test. You do not have time to look up each answer.
b. Carefully read the Chapter Summary, try to do the Conceptual Questions, and know the meaning of all the Key Terms at the back of each chapter.
c. Don't forget the index or the glossary.
d. Read the test questions carefully!
e. Go through the test once and answer all of the questions that you can. Then go back and do the other questions.
f. Mark on the test booklet: cross off obviously wrong answers, work the problems, and show your work. Circle the answer on the test booklet - that is the last resort if you have made a mistake on the answer sheet.
g. Carefully darken in the answer on the answer sheet, do not rip, mutilate, or fold it.
h. Check your answer sheet. Make sure you have answered all 50 questions.

MAKE SURE THAT YOUR NAME IS ON THE ANSWER SHEET AND YOU HAVE PUT IN YOUR FULL UNIVERSITY ID NUMBER-LEFT JUSTIFIED. NOTE THAT BOTH YOUR NAME AND ID # GO ON THE BACK! I will subtract points if this is not done.
BRING A PICTURE ID. I WILL ASK YOU TO PLACE IT ON THE TABLE IN FRONT OF YOU AND I WILL GO AROUND THE CLASS DURING THE EXAM CHECKING EACH ID.

Chapter 12: Star Formation
1. Note that some of the material in the first part of this chapter overlaps with the material in Chapter 11. It should have been one chapter.
2. Stars are born in Giant Molecular Clouds.
3. I discussed the material on page 226 in some detail. Remember that his arguments are true for the formation of the sun, NOT the collapse of Giand Molecular clouds.
4. What is meant by free-fall contraction? It is obtaining energy from the collapse - or contraction - of a cloud of gas under its own gravity.
5. What is a protostar? What is meant by the cocoon stage? As the protostar collapses, it is rotating which causes it to flatten into a disk with a bulge at the center.
6. What is meant by the birth line? How long did it take the sun to evolve from the birth line to the main sequence? How long for a 30 solar mass star?
7. What is a T-tauri star and where is it found? What is a T-association? An O Association? An Herbig-Haro object?
8. What is a bi-polar flow? Gas ejected from both the north and south rotation pole of the protostar.
9. What is HH 30?   AND WHAT DOES IT SHOW?
10. How long does a bipolar flow live?
11. Back to stellar energy sources. What is the CNO bi-cycle? Carbon is a catalyst in this cycle.
12. What are the three processes that transport energy in the interior of a star? Look at Figure 12-13.
13. What is the opacity of a gas?
14. Where is convection important in our own sun? In a 20 solar mass star?
15. Hydrostatic equilibrium means that all the layers in a gas or fluid are in balance: Pressure balances the pull of gravity.
16. What is meant by the onion skin model of a star?
17. How does the structure of a 7 solar mass star differ from that of the sun? For a 0.2 solar mass star.
18. The Orion Nebula is the closest Giant Molecular Cloud. Where is the Orion Nebula located in the sky?
19. Where are the Trapezium Stars?

Chapter 13. The Evolution of Stars
1. What are the four laws of stellar structure?
2. What kind of computer is shown in Figure 13-1? How does its speed compare to a modern, high end PC?
3. The Main Sequence is that region of the HR diagram populated by stars fusing hydrogen to helium in their cores. They have roughly the same composition from the center to the surface.
4. What are the most massive, least massive stars on the main sequence?
5. What is a brown dwarf? Have we found any?
6. A star is losing energy from the surface that must come from nuclear fusion in the deep interior. This is what causes the star to evolve.
7. Four protons are converted into one helium nucleus so nuclear fusion would leave empty space if the gas did not contract.
8. How long do stars of various masses live? I did this when we were talking about the sun too.
9. What will happen to the size of the sun as it uses up all the hydrogen in its core? What is such a star called?
10. What is the hydrogen shell source?
11. What is degenerate matter - I used the auditorium analogy to explain what happens.
12. The helium flash is caused by runaway nuclear fusion of helium to carbon --- the triple alpha process.
13. After the helium flash the star evolves to the horizontal branch.
14. The sun then evolves back up the giant branch and eventually becomes so luminous that it ejects gases in a planetary nebula.
15. What are the two major classes of star clusters? Where are each primarily found?
16. We use the main sequence turn-off of a cluster to determine its age.
17. Figure 13-14 shows how a hypothetical cluster evolves.
18. Figure 13-16 shows three different clusters with different ages.
19. The brightest stars in globular clusters are red, the brightest stars in open clusters are blue.
20. SKIP 13-4 for now.

Chapter 14: Star deaths.
1. What is a red dwarf? How massive is a red dwarf? How long to red dwarf stars live?
2. Do we expect to find red dwarfs that formed at the beginning of the galaxy and are still on the main sequence?
3. After the sun is a giant, it evolves to the horizontal branch and then up the asymptotic giant branch and gets very bright.
4. Light pressure drives off the remaining hydrogen surface layers and the hot underlying star ionizes the gas and forms a planetary nebula -- look at the pictures on page 271 and 272 and 273. I showed some more in class.
5. Skip thermal pulses - I did not mention them in class.
6. What happens to the central star after it has ejected a planetary nebulae? What is that object called?
7. The central part of a white dwarf is crystallized carbon. We know that by another name.
8. What happens to the size of a white dwarf as its mass gets larger? If its mass exceeds 1.4 times the mass of the sun?
9. The sun will eject a planetary nebulae in about 6 billion years.
10. Massive stars, much more massive than the sun, will fuse hydrogen to helium, helium to carbon and oxygen, carbon to neon and magnesium, and neon to silicon and finally silicon to iron.
11. The iron core then splits into helium and it implodes -- this produces a Supernova Type II explosion.
12. The most studied supernova remnant is the Crab Nebula which comes from a supernova that exploded on July 4, 1054.
13. There is another class of Supernova called a Type I. It comes from the evolution of a binary system -- we think.
14. What are the major observational differences between a Type II Supernova and a Type I supernova? I discussed this in class.
15. When did Supernova 1987A occur? What is its importance?
16. Read about radio and X-ray observations of SN remnants.
17. A local SN could be devastating to life on the earth.
18. Which bright star did I suggest could go SN in the near future - like tonight?
19. SKIP 14-3.

Chapter 15. Neutron Stars and Black Holes
1. What are the masses and sizes of neutron stars?
2. What is a pulsar? Who discovered pulsars? And when? I showed the actual tracing in class.
3. There is a pulsar in the center of the Crab Nebulae. It is losing energy that is heating the gas that forms the nebula.
4. What does a light house have to do with the observed emission from a pulsar?
5. Pulsars slow down - slowly!
6. Neutron stars in binary star systems can accrete hydrogen fuel which blows up in an X-ray burst.
7. Some pulsars are orbiting low mass objects about the mass of planets. Wouldn't want to live there.
8. The escape velocity is that speed required to actually escape from the planet or star or neutron star or black hole.
9. If we are sufficiently close to a black hole -- inside the event horizon -- we cannot escape no matter how fast we move.
10. I gave a formula in class for the size of the event horizon of a black hole.
11. How big would the black hole be if the Earth were squeezed down to where no light could escape?
12. How does the size of the event horizon increase as the mass increases?
13. We could approach to within a few thousand kilometers of a black hole and not be affected.
14. Skip the section "Black Holes Have no Hair"
15. Skip the section "A leap into a Black Hole"
16. Black Holes exist. Not only are there stellar mass black holes (I was part of a team that discovered one this semester), there are million solar mass black holes in the centers of galaxies.
17. Look at table 15-4. I was part of the team that discovered and studied V404 Cyg in 1989.
18. Gamma Ray Bursts do not belong in this chapter. They are giant explosions that are occurring in galaxies at the "edge" of the universe. We are finally beginning to understand them. They are probably associated with giant stellar explosions in newly forming galaxies. Or maybe not.

Chapter 16: The Milky Way Galaxy
1. I have already discussed much of the material in this chapter at one time or another.
2. The Milky Way consists of a flattened disk with a central bulge surrounded by a halo of globular clusters. It is probably not a coincidence that it resembles the solar system: planets and sun.
3. What is a kiloparsec? We will be using this unit a lot in the next few chapters.
4. Read about the history of the DISCOVERY of the galaxy as a collection of stars, gas, and dust.
5. Gas and dust dim distant objects so we didn't really understand how big the galaxy is until recently.
6. The disk component of the galaxy is relatively young - this is the flattened material where stars are forming.
7. It contains the spiral arms, giant molecular clouds, star forming regions, associations, dust, and gas.
8. The oldest objects in the galaxy are found in the Halo.
9. We can determine the mass of the galaxy from kepler's law.
10. What is a rotation curve? What does it tell us. It was NOT what we expected.
11. What is meant by stellar populations?
12. Which objects have the least amount of "metals." ? What do astronomers mean by "metals"? Be careful.
13. Which objects have the largest amount of metals.
14. Read how the galaxy formed. It is very similar to our discussion of how the solar system formed out of a rotation cloud of gas.
15. What are the spiral arms? How do we locate them? What are some spiral tracers?
16. Are the spiral arms real or only a pattern?
17. Stars are formed in spiral arms - the density wave theory actually gives us a good idea of how they are formed.
18. The nucleus of our galaxy is a strange and wondrous place. It contains a million solar mass black hole. We do not know how it formed there. We know it is there because we can see stars near the center orbiting at high speeds.