This course is a quantitative introduction to astronomy, with emphasis on stars, stellar structure and evolution, and the various scale structures that stars form, from binary stars to galaxies. We will begin by orienting ourselves to the scales and coordinates needed to understand the motion of objects in the sky, and learn how scientific revolutions of the past 500 years have formed our understanding of the universe. We will then introduce the solar system. Our main focus will then be the stellar life-cycle, starting with the birth of stars in the interstellar gas and dust, through their adulthood on the "Main Sequence," and ending with their return to interstellar gas and dust — sometimes in processes as spectacular as supernovae and leaving corpses as exotic as neutron stars and black holes. We will then study the structure of galaxies, and finally the evolution of the universe itself.
Prof. Yuk Tung Liu
320 Searles Science Building
Tel.: (207) 798-4167
email: yliu2@bowdoin.edu
Office hour: Tuesday 3:30pm-4:30pm and by appointment
The class meets at every Monday, Wednesday and Friday at 8:30am - 9:25am. Class attendance and participation in class discussions is expected and essential to success in this course. If you are feeling ill, please do not come to class, but send me an e-mail if you are able, and when you are better find a classmate to catch up on notes you will miss. You will need to visit the Health Center and/or contact your dean to be excused from handing in assignments on time due to health reasons. Please do not use a computer, or any electronic device other than a calculator during class unless you have discussed your need to do so with me. (For example, please do not text during class.)
Weekly homework sets will be due on Wednesdays at the beginning of class. They will be returned in the homework boxes on the third floor of Searles (outside room 307). To help us put your homework into the homework box, please use 8×11 paper without ragged edges.
Occasionally, there will be additional online homework posted on the Blackboard. The online homework will be short and less heavily weighted than the regular homework sets.
As with other physics courses, you are encouraged to discuss the problems with each other, since discussion often generates insight. (The best way to show you understand something is if you can clearly explain it to someone else!) The work you turn in, however, must be your own — to hand in a word-for-word, equation-for-equation copy of someone else's homework as your own is a violation of Bowdoin Honor Code, and will be treated as such.
Your solutions will be read by a grader or the instructor. Explain your problem-solving procedure in words; equations alone are not sufficient. How you do a problem is much more important than obtaining the correct numerical answer. If you are confused about some aspect of the problem, identify that aspect. If you make any assumptions, state them. Hand in as much as you can accomplish on each problem. Again, the thought process is more important than the final answer, so even unfinished problems are worth handing in.
The homework will count for 30% of your final grade. Late assignments will be penalized 10% per day, or portion thereof, until the next class, after which they will not be accepted.
There will be one daytime observing project: tracking sunspots with a "Sunspotter" telescope. Instructions will be provided later. The project will count for 10% of your final grade.
There will be several night-time observing sessions throughout the semester, where you will have chances to use telescopes to watch planets, nebulae, star clusters and galaxies. You are strongly encouraged to come to these observing sessions, although it is not mandatory.
We will have two in-class midterms, on March 1 and April 19, each one counting for 15% of your final grade. All tests will be closed book and closed notes, but formula sheets will be provided. The final exam will be on Thursday, May 15 at 2:00pm, and will count for 30% of your grade. Please note this date on your calendars, and inform anyone making travel plans for you now that you need to be present for the final exam on that day.
Grades will be given on an absolute scale, based on your accumulation of points:
Homework: 30%
Midterms: 30% (= 2×15%)
Observing project: 10%
Final exam: 30%
If you end up on the borderline between two grades, a number of other factors will decide whether you will get the higher or lower grade. These factors include consistency, effort, and in-class participation.
Class times: MWF 8:30am - 9:25am at Searles 315.
| Dates | Topics | Chapter | Homework Due |
|---|---|---|---|
| Jan. 21 - 25 | Introduction, Celestial Sphere | 1, 2 | |
| Jan. 28 - Feb. 1 | Seasons, Eclipses and the Motion of the Moon | 2, 3 | 1 |
| Feb. 4 - 8 | Gravitation and the Waltz of the Planets | 4 | 2 |
| Feb. 11 - 15 | The Nature of Light | 5 | 3 |
| Feb. 18 - 22 | Optics and Telescopes | 6 | 4 |
| Feb. 25 - Mar. 1 | Solar System, Midterm #1 | 7 | PE #1* |
| Mar. 4 - 8 | Our Star: The Sun | 16 | 5 |
| Mar. 11 - 22 | Spring Break | ||
| Mar. 25 - 29 | The Nature of Stars | 17 | 6 |
| Apr. 1 - 5 | The Birth of Stars | 18 | 7 |
| Apr. 8 - 12 | Stellar Evolution | 19, 20 | 8 |
| Apr. 15 - 19 | Supernovae, Gamma-Ray Bursts, Midterm #2 | 20 | PE #2* |
| Apr. 22 - 26 | White Dwarfs, Neutron Stars, Black Holes | 20-22 | |
| Apr. 29 - May 3 | Galaxies, Hubble's Law | 23, 24 | 9 |
| May 6 - 8 | Cosmology: ΛCDM Model and Beyond | 26, 27 | 10, PE #3* |
| May 15 | Final Exam at 2pm | ||
* PE = practice exercise.