Astronomy - Fall 1998

This course will provide a broad overview of our knowledge of the universe. This course is intended for non-science majors. The emphasis will be on the reasoning and evidence behind our current knowledge of and theories about the nature of the Universe. We will begin with a brief description of the naked eye night sky. Next, we will study the nature of gravity. We will then learn about objects in the universe, beginning close at home with objects in the solar system, and then extending outward, first studying stars, then groups of stars, and the large scale structure of the universe. We will end by looking at theories of the origin of the universe.

There will be three lectures per week, and one discussion section. There will be two midterms and a final. The exams will consist of essay questions and problems. There will also be a set of weekly homework problems. The final pass-fail grade will be determined on the basis of 40\% final, 25\% each midterm, and 10\% homework.

I will keep two copies of my lecture notes on two hour reserve in the Science Library. In addition, copies of my lecture notes will be available from the campus copy center

I hope to organize a field trip to Lick Observatory sometime during the quarter. This may provide an opportunity to visit a working observatory and to observe celestial objects through a large telescope.

The following are the topics to be covered:

• Introduction and Overview - 1 lecture
• Observing the Sky, - 2 lectures
• Gravity, - 2 lectures
• The Terrestrial Planets - 3 lectures
• The Giant Planets - 2 lectures
• Meteorites, Comets, and Asteroids - 1 lecture
• Light, Atoms, and Telescopes - 3 lectures
• The Sun - 2 lectures
• The Nature of Stars - 2 lectures
• The Birth, Life, and Death of Star - 3 lectures
• Galaxies - 3 lectures
• Cosmology - 3 lectures
• Life in the Universe - 1 lecture

Astronomy 11 Gravity: the Universal Glue

INTRODUCTORY REMARKS:

Gravity is one of the most obvious and yet at the same time one of the most mysterious forces in the Universe. It is by far the weakest of the four fundamental forces found in Nature, yet the first one we encounter as we try to struggle to our feet for the very first time. It not only holds us down to the Earth, but it reaches across and organizes structures out to billions of light years' distance. It keeps the Moon in orbit around the Earth, the planets round the Sun, the solar system moving around in the Milky Way galaxy. Small and large star clusters are held together by mutual gravity, even as they themselves are held in sway by their parent galaxy. Groups, clusters and superclusters of galaxies all pull on one another, and finally the grand design of the whole Universe itself reveals the effects of gravity operating everywhere.

Newton's basic "Law of Gravity" has been known for over 300 years, but the mysterious observations of planetary motion that he was trying to understand go back to classical times. In this course we examine those motions, and the ideas of the structure of space and time to which they ultimately led. We learn of the great triumphs of Newton's ideas - basic gravity itself, its role in producing the tides, even the prediction of a previously unknown planet. But then we'll find that subtle things in planetary motion could not be explained, and that that led on to Einstein's revolutionary ideas embodied in General Relativity, with its Star Trek-like concepts of Space and Time Warps, and exotica like Black Holes. And, of course, we'll also study things a bit closer to home - the role of gravity in the structure and evolution of stars like our own sun, and other stars and star pairs small and large.

There are a lot of fascinating and mind-blowing ideas in this course, and also a lot of hard work. By the very nature of the topics to be covered, you'll need to be on top of your High School math, particularly algebra and geometry; the ability to use that math, to visualize well, and to be able to draw neat sketches and diagrams is almost essential. It's absolutely pointless to take this course if you don't feel confident with your math. Good math skills are taken as a given in this course, so we can press on to learn neat new things and not turn it into a remedial math course.

Not to labor the point, this is not a "mick" course, nor a course you take thinking "Well, I really should have taken Astronomy 2 but it didn't fit into my schedule!"

Recognizing that, however good people's basic math skills may be, they probably won't have had to use them to organize and analyse facts about the world, I run two problem and homework discussion sections in which I try to help you in these areas. These are an essential part of the course itself - so don't take the course if you can't make one of those times. (We will see whether adjustments in those times might be desirable at one of the first two classes.) I find that setting up and solving problems is one of the weakest elements with which intending science majors enter the university - so I do my best to help you develop skills that will serve you well later.

The course is mainly intended for those who will major in the sciences; however, I've had some really outstanding non-science students over the years, whose natural talents and interests have helped them to succeed.

What follows is the typical General Information and Syllabus available at the first class. Note that some dates (midterm, final exams) have not been set yet.

INSTRUCTOR: John Faulkner, 403 Kerr Hall, email johnf@ucolick.org

LECTURES: Tuesday and Thursday 2-3:45 (NS Annex 103)

SECTIONS: Wednesday 9:30-10:40 and 11-12:10 in Thimann 103A

THE COURSE: This is a lower division course designed for intending mscience majors.

Non-science majors should not be taking this course unless they have a rare interest in the physical world, and can view high-school algebra and its application to the world without going into a catatonic state. Please see me before embarking on this course.

The course deals with motion and gravity, broadly conceived. Thus we shall find our concerns ranging from the insights of early Greek astronomy, through the triumphs of medieval and renaissance astronomy, Newton's synthesis and the great flowering of understanding, to Einstein's challenging, conceptual revolution, and the bizarre world of stellar evolution, pulsars, black holes, quasars, cosmic radiation and universal expansion, which puts us at the frontiers of current research. Quite a tall order!

Though some parts of the course will be descriptive in character, the main thrust will be to show not only what principal things we have learned about the gravitating, astronomical universe, but how these things were learned. There will necessarily be considerable emphasis on the physical processes believed to be operating in various objects, and therefore some development of basic concepts in physics will be an important part of the course. On the other hand, astronomy involves so many parts of physics that some discussions must be sketchy and highly selective, so that we may concentrate attention on the additional interactions of gravity with these matters.

There will be a fair (and perhaps at times heavy) amount of algebra and geometrical concepts in the course. This is because the quantitative consequences of a theory cannot be deduced from a warm, amorphous Santa-Cruzy glow of grand and general concepts, fuzzily connected. A knowledge of (or concurrent enrollment in a class on) elementary calculus could be an advantage, although not essential.

Upper division physics majors here for an easy ride should instead consider attending one or more of the courses designed for their benefit, e.g., (examples from 111 series).

Non-science majors should attend either the one-quarter quickie: 2: Overview of the Universe (FWS) or the somewhat more thorough courses which, while independent of one another, may be taken to form one year's study of astronomy, e.g., 4: The Stars (W). There is also course 80A: Space-Age

There will be weekly problem sets, of "open book" type. Feel free to discuss appraoches and methods with your fellow students if that aids your personal learning. However, please set pen to paper independently. It is your thoughts, distillations, mode of expression and ultimately your integrity that are important. Be literate and self-critical, please! In general homeworks will be issued and due back on Thursday. A minimum of 5 homeworks must be submitted; try to do them all.

Homework is taken into account in reaching Pass/Grade decisions. In marginal cases it can be crucial.

Experience in teaching this course the last few times has shown that students benefit greatly in learning the material and in improving their general problem-solving techniques through regular attendance at less formal and structured homework discussion "sections." Some have shown a truly dramatic improvement during the course of the quarter. I am therefore requiring that students attend such a section for at least one "hour" per week. If unable to attend during the times stipulated, see me to make other arangements.

Midterm in class, closed book (date). Final (date and time). Exams will count approximately 75% toward the Pass-No Record or Grading decision.

TA's in larger classes schedule fairly frequent observing sessions on campus which we may be able to attend. There may also be a field trip (transportation to be arranged among class members) to Lick Observatory on Mt. Hamilton, weather permitting.

A detailed syllabus, keyed to references, will be found on page 6. References should be consulted, and preferably studied, prior to attending the related classes.

Required and other useful books are discussed on pp. 3-5. Those marked with an asterisk (*) will be placed on 2-hour reserve for your use, in the Science Library. The others may be there, also.

Copies of former class notes will also be placed on reserve. These should be particularly useful for the early part of the course, where they are most detailed, also for certain aspects of the physics and evoltion of stars. Warning: (i) lecture numbers and section references to books will not necessarily correspond to current practice or editions, so check the topics and relevant referneces in the syllabus; (ii) the notes are not a substitute for attending class.

An essential "reader," containing copies of frequently used or important diagrams, and film notes (see below) is available from the Campus Copy Center in the Communications Building, cost $7.59. It is called "Visual Aids for Astronomy 11." You must get this, as soon as possible.

Extensive use will be made of the BBC Open University/UC 13-part film series "Understanding Space and Time." Typewritten notes (plus a few diagrams) based on these films are included in the reader. They can remind you of film content and/or serve as a basis for your own annotations. Video copies of the movies may also be placed on reserve at "Library Recordings," 1st floor, McHenry Library; wait for announcements.

Quantitative mathematical arguments are an important component of this course. You must be competent and confident in handling high school algebra (not merely have scraped a pass years ago). Familiarity with circular and/or spherical geometry and elementary trigonometry would also be an advantage. Explicit calculus will not be used, but several of its ideas will appear from time to time. Please note: Many of the physical or conceptual ideas that we will encounter later in the course are apparently so strange and bizarre that they themselves will require a good deal of thought and contemplation. It would be silly and counter-productive to be worrying at the same time about basic math skills.

It is essential that poor math preparation not get in the way of ideas in this course. Therefore, there will be a very basic math test during the second class. You must take this test and do sufficiently well, to take this class. Let me re-emphasize: some of the ideas in this course are strange enough that they will take some time to master. You should not be having to struggle with mere mathematics at the same time. I will not let you continue if you don't do well enough on the test.

No one book or combination of two books "is the course." The problem with books on this subject is that they tend to be either encyclopedic and descriptive, beautifully illustrated but devoid of mathematical analysis, or they become more limited in scope, contain some analysis, but skimp on the illustrations.

Since we deal with objects of such compelling beauty in astronomy, I require one relatively up-to-date encyclopedic text (Pasachoff) written primarily for the non-science student, which my notes supplement analytically. However, because it contains material related to the films, I also recommend a less visually exciting book (Abell, Morrison and Wolff, etc.). Since both sets of books will be on reserve, I'd appreciate your considered comments at quarter's end. If you are well off, or simply like to read, other books can be recommended for some aspects of the course or for sheer interest. See the discussion which follows.

• Pasachoff, Astronomy: From the Earth to the Universe (5th ed., 1997).
  • Fairly up-to-date, profusely illustrated, quite good verbal descriptions of some phenomena and their explanations, "glossy" on others. Rather weak on history, absolutely no mathematical analysis. This book is the "observational material," which my notes will supplement.

• Abell, Morrison and Wolff, Exploration of the Universe (5th ed., 1987; 6th ed., ?) and Morrison, Wolff and Franknoi, Abell's Exploration... (7th ed., 1995).
  • A full-length text with a small number of mathematical derivations which the non-science majors for whom it was written nevertheless find daunting. A trifle on the dull side because George's publishers insisted on removing every joke in his original manuscript (though they failed to catch one on p. 29 of Realm [1976; below], they duly completed their deadening job in 1980). Check Pasachoff for alternate discussion and comparison.
• Epstein, Lewis Carroll (!), Relativity Visualized (1983; paperback reprint 1994).
  • An idiosyncratic, unconventional text which offers unique and helpful ways of visualizing some of the effects of "curved space-time." Emphasizes an aspect often not appreciated even by the professional physicist or relativist--that local Newtonian gravity is due entirely to the uneven running of time (alone!), and has nothing to do with the curvature of space per se.
• Gamow, Gravity: classic and modern views (1962); reissued as Gravity (1969: Anchor Doubleday paperback, $2.50), but out of print.
  • A beautiful little book (under 160 very small pages!) written with George Gamow's characteristic insight and humor. While now dated ("modern," meaning 1962, was pre-black holes and pre-discovery of the background radiation, which Gamow had predicted!), this book is a minor classic on the subject.

• Smith and Wood, Understanding Space and Time (1982).
  • This book was produced as a printed complement to the film series I will be showing. It contains brief descriptions of each film, amplifications on points of interest, and groups of related readings. Much of this should be useful, although my accounts of the later movies (in the "reader") may be more verbatim.
• Nicholson, Gravity, Black Holes and the Universe (1981).
  • Another very fine book, not a text, but with unusually thorough discussions, interesting historical vignettes, and very much up with modern research at the time of going to press. A "good read" if the subject interests you outside of clas requirements.
• Harrison, Cosmology: the science of the universe (1981).
  • Another very fine book, more suited to science majors, with a modest amount of analysis. Were this just a course on cosmology (and black holes), this would be the book I would use at this level. Very few (12?) photographs, unfortunately, but profuse and superbly executed line drawings, sketches, etc., many of which make their point compellingly. Also noteworthy are his "Reflections" at each chapter's end, which are worth reading in themselves. Only a reluctance to ask students to spend $60 (>$100 now?) on books stopped me from requiring this throughout the '80's and early '90's.
• Hawking, A brief history of time (1988).
  • A "popular" account of time, space-time, gravity, cosmology, the origin of the Universe, etc. by one of the most amazing and outstanding individuals of our time. Mind-bending, even if it "contains only one equation." On NY Times best-seller list for years.
• Shipman, Black Holes, Quasars and the Universe (2nd ed., 1980).
  • Some earlier instructors in this course have used this (or the 1st, 1976 ed.) for the second half of the quarter. They feel it gives a good account of the thrust and parry of modern research. A descriptive book with a fair number of diagrams and photographs. I feel it would be better with some supporting analysis. As a stellar evolution enthusiast, I find his description of this topic is rather weak.
• Hoyle and Narlikar, The Physics-Astronomy Frontier (1980).
  • A "modern" text with some fascinating account of the development of various post-World War II branches of the subject. Gets across a lot of the spirit with which a modern astrophysicist views the application of physics to astronomy. Hoyle (my own Ph.D. research supervisor) has had an enormous impact on much that is now taken for granted in the subject. The book sometimes overemphasizes his own rather idiosyncratic way of viewing things. This is particularly the case with the closing sections on cosmology.

OTHERS:

• Abell, Realm of the Universe (1976, 2nd ed. 1980).
  • A shorter version of "Exploration."
• Berry, A short history of astronomy (1898, Dover reprint 1961).
  • Largely a dry as dust but sometimes interesting account of astronomical history and some of the cultural and scientific circumstances surrounding major discoveries.
• Pasachoff and Kutner, University Astronomy (1978).
  • An expanded version of the 1st ed. of "Contemporary Astronomy." Useful for some analytical treatments of matters in the early parts of the course but, because of its date, not so current in the rest.
• Pasachoff, Astronomy: From the Earth to the Universe (3rd ed., 1987).
  • A short and re-ordered version of the 3rd ed. of "Contemporary Astronomy," slightly more current.
• Hoyle, Astronomy (Doubleday 1962 and Macdonald 1962).
  • Masterly exposition, unusual insight. Not really a University text, but a superb coffee-table book, excellently illustrated, and with convincing historical and scientific analyses. Was available fairly cheaply until recently through remaindering outlets.
• Gamow, My World Line: an informal autobiography (1970).
  • Really unrelated to the course, but showing superbly what it was like to be a top-notch scientist earlier in this century, with occasional astrophysical connections (Gamow's "tunnelling" of helium nuclei in alpha-particle decay, when reversed, explains how the nuclear reactions occur which fuel all stars, including the sun).

The first seven lectures deal with our growing understanding of motion and gravity at a much more thorough level than Pasachoff's book. My lecture notes, on reserve, should be helpful here. the remaining lectures mainly follow Pasachoff's treatment more closely, with mathematical amplification. However, Pasachoff treats relativity far too cursorily. I shall give treatments similar to those found in the film series, "Understanding Space and Time" and in the book by Abell et al.

In what follows, P=Paschoff, Astronomy: From E to U (5th ed., 1997 version), and A=Abell, Morrison and Wolff, Exploration of the Universe (5th ed., 1987).

Remember Chapter references are minimal; you can always read more! Stay ahead of the game by reading in advance! That way, you'll understand lecture topics much better.

1. The scope and scale of astronomy P1, A1

2. Familiar astronomical phenomena and

triumphs of Greek astronomy P 2.1-2.3, 6, 7.2-7.5, 9.1

3. Renaissance astronomy; problems of P 2.4-3.2, 13.2

motion and dynamics A 2, 3, 4

4. Newton's law of gravity and its P 3.3 (18.4), 8.1- 8.3, 15.1-15.3, 16.1

consequences; orbits, tides, precession,

discovery of Neptune A 4, 5, 17.3

5. Light, atomic structure, spectra; special P 4 (5), 23

relativity, E = Mc2 A 8, 23, 24, 11

6. Stellar distances and motions, the HR diagram; P 24, 25

binary stars, stellar statistics, clusters A 22, 25, 26, 31

MIDTERM EXAM; covers topics 1-4, part of 5

7. The physics of stars; the main sequence P 21, 22, 26

(the stellar prime of life) A 28, 29, 30

8. Stellar evolution; beautiful young stars P 27-29

and degenerate dwarfs, red giants, cataclysmic A 30-32

stars, supernovae, novae, dwarf novae, pulsars,

neutron stars

9. General relavitity, curved space, black holes P 30

A 11, 33

10. Our Galaxy and other galaxies, clusters of P 31-35

galaxies, discovery of the expansion of the A 34-37

Universe, quasars

11. Cosmology: Big Bang and other ideas, universal P 36, 37

background radiation, the first 3 minutes, the A 37

uncertain future

FINAL EXAM

"Principles of Stellar Evolution and Nucleosynthesis," by D. D. Clayton (MacGraw-Hill, 1968). Also paperback ed. "Structure and Evolution of the Stars," by Martin Schwarzschild (Princeton, 1958).

"Single and Binary Star Evolution," by I. Iben (Ap.J. Suppl. 76, 55, 1991).

1. Basic observational data element abundances, H-R diagrams, masses, rotation, age
2. Equations of Stellar Structure differential equations for hydrodynamics and hydrostatics virial theorem, homology relations
3. Stellar Physics radiative and convective transport equation of state, opacity nuclear reactions, primarily hydrogen burning
4. Simple Stellar models polytropes, white dwarfs
5. Stellar Evolution - single stars pre-main sequence contraction, comparison with observations properties of zero-age main sequence, mass-luminosity relation
   • Evolution of the sun
     • main-sequence evolution, solar neutrino problem, red giant formation
   • Evolution of other low-mass stars of Pop I
     • dependence on mass, thermal instability, mass loss, helium burning planetary nebula and white dwarf phases
   • Evolution of Pop II stars of low mass
6. Current topics in Stellar Evolution

• Problem assignments
• Calculation of a stellar model
• Brief review (written) of a recent (last 5 years) research paper in the area of stellar structure and evolution
• Ten (10) minute class talk on the above paper--to be given during the last week of quarter
• Final quiz or problem assignment

Revised 7/15/04.