Astronomy 101
Fall 2007
Haverford College
Syllabus
Lecture: MWF 11:30-12:30, Sharpless Auditorium.
Discussion Sections: to be scheduled later; roughly once a week for each of you.
Occasional evening labs: to be scheduled soon.
Instructor:
Bruce Partridge
email: bpartrid@haverford.edu
phone: 610-896-1144
office: Observatory
office hours: probably on Mondays and Thursdays (to be confirmed)
There are several good reasons, each of which has helped determine the nature of Astro 101 as it will be taught this term.
1. Despite its recent explosive growth, astronomy is a science that can be covered in a single term.
2. It therefore serves as a quick and useful introduction into the way physical scientists look at the natural world. Astronomy provides many good examples to illustrate basic scientific principles.
3. The impact of astronomical discoveries and theories on the cultural outlook of Western civilization has been and is still very large.
4. While astronomy is the oldest science, it is also among the youngest. New discoveries pour in, yet there is still room for fundamental theories to be invented.
5. Curiosity. Why are the stars different colors? Why is the full moon so bright in winter? What creates the rings around Saturn? How long will the Sun last? What are black holes? Is time travel realistic? What is the future of the Universe?
I list below some very general goals I have for the course (and hope you share). These are spelled out in more detail in a report on “Goals for ‘Astro 101,’” a copy of which is on reserve. I hope you will gain:--
And finally, I hope you leave Astro 101 more confident of your own critical faculties and more interested in science and in astronomy in particular.
1.) The course will begin with a survey of ancient astronomy, emphasizing particularly the contributions made by the Greeks: their attempts at natural explanations of celestial phenomena and their application of geometry to astronomy. We'll later ask why Greek science ossified after its promising beginnings.
Next, we'll study the Copernican revolution as a paradigm of intellectual revolutions. Why was there so much opposition to the idea that the earth moves round the sun? What were the crucial astronomical observations that carried the day?
Kepler’s descriptive laws of planetary motion and Newton's more general laws capped this revolution. We'll study the motions of the planets as determined by these laws.
2.) The surface, atmospheric and internal properties of the planets are treated next. We will look particularly at clues to the evolution of the solar system and to the evolution of the surface properties of the inner planets. In this section, we'll make considerable use of the results of past and present U. S. and Russian missions to the planets.
3.) While we have never been able to lure any stars into the laboratory, we feel we know a great deal about them. In the third section of the course we will consider the ways in which we gather information about the stars and what this information tells us about the complicated evolution of the stars from a cloud of gas and dust to a sometimes catastrophic end. One possible endpoint, a massive explosion known as a supernova, will be considered in detail. We will also discuss stellar remnants: white dwarfs, neutron stars, pulsars and Black Holes.
4.) Stars make up galaxies; however the existence of other galaxies outside our own was established only in the 1920's, and the origin of galaxies in the universe is still not fully worked out. In this section, we will first discuss the properties of the Milky Way, our own Galaxy, and following that the large zoo of other galaxies in the universe. Particular emphasis will be on the evolution of galaxies.
5.) The final section deals with one of the great discoveries of the twentieth century: the Universe as a whole has a history. We know it started in an immense explosion; we know that it is now expanding. Although we have the mathematical tools to predict its future, we still don't know for sure whether it will continue to expand forever. As part of this inquiry we will discuss the formation of elementary particles and matter in general.
Required text 21st Century Astronomy by J. Hester and a group of other well-known astronomers.
Optional text “Discoveries and Opinions of Galileo,” translated by S. Drake. A variety of optional readings will be placed on reserve in Magill Library.
Tutoring Tutoring is available if you are having problems with the course. See me or your dean for how to get set up with a tutor.
CD-ROM Your textbook comes with a CD-ROM, compatible with both Macintosh and Windows. It includes some nice animations and a “virtual planetarium” which shows you the night sky for any time and any location on earth. The CD-ROM will mostly be a supplement for you to explore on your own.
E-mail If you have a question about the course, or wish to arrange a meeting with me outside of office hours, email is the best way to contact me. I will also send email to the class from time to time with various announcements (such as canceling an evening lab if the weather suddenly turns bad). These announcements will also be made in lecture, but if you check your email regularly, you will be better informed.
The whole class will meet three times a week. Some of this time will be traditional lecture format (the “sage on the stage” mode, where the professor stands in front and talks; you listen and take notes), but I plan to include regularly some non-traditional activities that will help you get more involved with the material, such as demonstrations, multi-media shows, working through problems in small groups, discussions, etc. Come to class meetings prepared (do the assigned reading ahead of class) and prepared to participate.
In addition to the three weekly lectures, I will arrange discussion sections of 12-15 students that will each meet once a week. These will provide an opportunity for you to interact with the professor and each other more than is possible during “lecture.” You’ll get the most out of these small group meetings if you attempt the homework beforehand and bring questions you have about the homework to the meetings. Occasionally I will take some time during these meetings for labs or discussions of interesting topics not covered in lecture.
Homework Assignments will generally be due on Fridays.
Math level
Since math is an essential and powerful tool for doing science, I want you to use it yourself in this course. The only mathematics required will be straightforward algebra and a bit of trigonometry. See the Math “Bag of Tricks” for a review of math I expect you to use. Experience shows you won’t be troubled by the math; what makes Astro 101 demanding (and it is demanding) is the abstract thinking required, not the algebra.
There will be three exams which will stress reasoning and problem solving rather than memorization. The exams will be take-home and open-book (and therefore more searching), and will give you a choice of questions.
Several labs will be assigned during the semester, to give you a chance to do astronomy yourself. Some of these you can do on your own with no equipment except your eyes and your notebook. Others will require working with a partner, using some basic equipment, or using data and simulations on the Internet. Twice during the term I will have everyone (in shifts) use the 8-inch portable Meade telescopes for labs. Times for this will be scheduled as we go, to accommodate both the weather and your schedules.
I would like to have you use the telescope more often, but the large size of the class and the small number of clear nights make this very difficult. If you want to spend more time at the telescope, visit a star party (see below), or come to the observing nights run by the Astronomy Department.
You can replace one homework assignment with a visit to the Delaware Valley Amateur Astronomers. You can attend either a Star Party or one of their monthly meetings. They will have several telescopes set up and astronomers eager to show you the moon, stars, and planets, and answer your questions. Star parties are canceled if the skies are not clear (see their Web page for further details).
Your grade will be calculated as follows: 25% for homework, 15% for labs, and 20% for each of three tests.
Discussions with your fellow students regarding course material are strongly encouraged, since by asking questions of each other and explaining concepts to each other you will come to a better understanding of the material. In order to learn the most from homework assignments, follow these guidelines:
1. Spend a significant amount of time on your own first. Make a thorough attempt at each problem, referring to the text, the “Bag of Tricks” and “Seven Steps to Solving Physics & Astronomy Problems,” etc.
2. Then feel free to discuss the problems with your classmates or professor.
3. After receiving assistance, carefully write up the solution in a way that makes sense to you. Make a note on your assignment regarding the collaboration or assistance: who did you work with, on which problem and how much help did you receive?
4. When you receive the graded homework back, read the comments from the grader. Make sure you understand what the correct solution is by discussing the problem with your classmates or professor, or by checking the solutions on reserve in the library.
Remember, on the exam you will have to work on your own, so it is in your best interest to make sure you fully understand each homework assignment.
I’m serious about due dates. It’s important not to get behind in the course. Thus, I’ll only accept serious excuses for late assignments: a death in the family, illness, or a religious holiday. Please inform me ahead of time if at all possible if you’ll be turning in work late. Otherwise, homework will be graded down.