ASTR121, Spring 2008
Introduction to Astrophysics - Solar System

Prof: Doug Hamilton
Phone: (301) 405-1548
Office: CSS 1245
Office Hours: TuTh 12:15pm-1:15pm or by Appointment
Textbook: Universe, by Roger A. Freedman and William J. Kaufmann III (eighth edition - ISBN 0-7167-8584-6). Note: for an additional fee, you can order the e-book and/or Starry Night software but I will not require these for the class. This book was also used for ASTR120 in fall 2007.

Course Description:

Welcome to Astronomy 121! After completing our survey of the Solar System in ASTR120, we now turn our attention outward, ranging far beyond the furthest explorations of our spaceprobes. We will learn about the life and death of stars, massive stars, dim stars, burned-out stars, and singularities in spacetime that destroy everything in their paths. We will study the behavior of matter at extremely high and low temperatures and densities. We will investigate the strange physics that occurs at very small size scales and very large speeds. Finally, we will explore our galaxy and others beyond it, and we will probe what the universe looked like when it was born, how it has evolved, and what will happen to it in the distant future. After successfully completing ASTR120 and ASTR121 you will be a true Master of the Universe.

Class Organization:

Lectures meet in CSS 2428 on TuTh from 11:00am to 12:15am. Lectures led by the professor will include discussions, worked examples on the whiteboard, slides, videos, etc.

The Discussion Section meets in CSS 2428 on Fridays from 2:00pm-2:50pm starting on Feb. 1. Discussion sections are led by graduate student Teaching Assistant (TA) Mia Bovill. The section provides a more informal environment for further developing the material taught in class.

The Lab meets in CSS 1109 on Mondays from 11:00am-1:00pm (section 0201) and on Mondays from 2:00pm-4:00pm (section 0101) starting on Feb. 4. Labs are led by graduate student Teaching Assistant (TA) Mia Bovill. The Lab allows students to explore concepts discussed in class in small interactive groups.

The Class Web Page is a useful resource that we will use extensively. The website contains links to course information, supplementary readings, and interactive programs to make ASTR121 fun and to help you learn. You will be able to monitor your estimated grade in the class as the semester progresses, and communicate with other students, the TA, and the Prof. on the class bulletin board. In addition, this site is also a gateway to many other astronomy links, including sites with up-to-date astronomical images that are made available to the public from telescopes in space and on the ground.

Course Expectations:

Attendance: In order to succeed in this course, I expect you to attend all lectures, discussion sections, and labs. This is very important! The material on the homeworks and exams are based upon the material covered in the text and class meetings. If you have to miss a lecture, section, or lab, be sure to look at another student's notes and make sure that you understand what was covered. Make sure that you understand our policy for make-up work. See me or the TA if you have questions. There will be times during the semester, in class meetings, when the TA or I will ask for written responses to questions. Your written answers will count towards your grade in the class.

Preparation: I expect you to be prepared to work. You will understand the lecture more easily if you preview the reading assignment. A more careful reading is recommended after lecture. You should study your class notes sometime before the next lecture to make sure that everything is clear. I encourage you to ask questions in class, in section, during office hours, or over email.

Study Habits: Study wisely and ask for help if you need it. If you just cram the night before the exam, you probably will not do very well. It is better (and easier) if you keep up with the material on a daily basis. Make it a point to read the chapters in pace with the lectures; this is one of the best study habits you can have. Taking a page or two of notes on each chapter as you read it is also a good idea.


I grade on a point scale with different assignments weighted as shown in the table.

Cover Sheet
Exam I
Exam II

Letter grades will be assigned based upon your curved cumulative score. Here is how your grade will be determined from your point total in the class.

Letter Grade
Course Total

The point scale makes it possible for everyone in the class to do well. For example, if everyone scores above 80% in the course, you would all receive a B- or better letter grade. I do use +/- modifiers: you will earn a "+" if you are in roughly the upper 1/3 of students with the same letter grade and a "-" if you are in the lower 1/3. I may adjust the number of points required to get a given grade depending on the class averages; however, any adjustment will make it easier to get a given grade, never more difficult. You can monitor my current estimate of your grade from the class webpage as the semester progresses.


There are a total of eleven homeworks in this course; all will be posted to the Assignments link from the class website. Please type or writeup your assignments neatly. Homeworks are due on Thursdays at 11:00am. Late homeworks will be assessed a late penalty and, if very late, may not be accepted at all. Talk to the TA before the due date to minimize these penalties. Graded homework papers and solution sets will usually be distributed in the section or lab following the due date.

Although you may discuss the homework problems with your friends, the final writeup must be in your own words. Copying from a friend's homework, copying from a book, or allowing a friend to copy your homework is academic dishonesty and will not be tolerated in this class. If you consult a reference other than the course text, please acknowledge it in your homework - this includes websites!

Discussion Section and Lab

A weekly hour-long discussion section (beginning Friday Feb. 1) and a two-hour long lab (beginning Monday Feb. 4) are integral parts of this course. Both section and lab are run by an experienced TA, Mia Bovill, with just general guidelines from me; they will typically include a review of lecture material, presentation of problems and material not covered in lecture, exercises and quizzes, computer projects, hands-on experience with instruments etc. Both section and lab serve as forums to enhance your understanding of the course material. Your TA is an excellent resource; get to know her and use that resource! Homeworks, Exams, and other class work will be returned to you during either discussion section or lab. Please attend all of these meetings. If for some reason you have to miss a discussion section or lab, talk to Mia before your absence and get permission from her to do a makeup assignment. Mia maintains a website with more information about section, lab and classwork: .


There will be two in-class midterm exams which are closed book with no notes, no calculators, and no electronic devices allowed. Each exam will consist of short answer questions, problems, and several longer essay questions. These exams are incremental (i.e., non-cumulative) checkups on how well you have learned the material. The schedule of lectures included in this syllabus shows what material will be covered on each exam. If for whatever reason, the University is officially closed on the exam date, the exam date shifts to the next lecture date.

According to University rules, the final exam for this course will be held on Thursday, May 15 from 8:00am to 10:00am in CSS 2428. This final exam is cumulative, that is, it will cover all material discussed in this course. However, the the weight on the last several chapters not covered by the midterm exams will be higher than on earlier chapters. The final will include short answer, essay, and problem solving questions with the exact combination to be determined. The final exam is also closed book with no notes, calculators, and electronic devices allowed.

Missed Exams

If you are not able to take an exam due to illness or other legitimate reasons (as outlined in the Academic Info section of the schedule of classes) and you wish to take a make-up exam, you must

Extra Credit

There are several ways to earn extra credit in this class: There will be no extra credit assignments besides those listed here.

Core Requirements

ASTR121 is intended for science majors and requires a solid high-school level science and math background. This course satisfies the CORE Distributive Studies requirement for a lab physical science course (CORE code PS). ASTR120 counts for non-lab physical science CORE credit.

Academic Integrity

The University of Maryland, College Park has a nationally recognized Code of Academic Integrity, administered by the Student Honor Council. This Code sets standards for academic integrity at Maryland for all undergraduate and graduate students. As a student you are responsible for upholding these standards for this course. It is very important for you to be aware of the definitions and consequences of cheating, fabrication, facilitation, and plagiarism. For more information on the Code of Academic Integrity or the Student Honor Council, please visit

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