Introductory Astrophysics; Solar System

(Fall 2009; Prof. Reynolds)




Prof: Chris Reynolds

Phone: (301) 405-2682


Office: CSS 1243

Office hours: Thursday 2.30-3.30pm, or email me for an appointment

Textbook: Universe; Freedman & Kaufmann; ISBN0-7167-8584-6 (8th edition)


Course description


This course presents a broad introduction to the science of astronomy and astrophysics.  It is designed to be a two-semester sequence with the first semester (ASTR120) concentrating on our Solar System and the second semester (ASTR121) focusing on stars, galaxies and the wider Universe.  The intent of this course is to give the student a solid background in the primary physical concepts relevant to astronomy and astrophysics, and a broad exposure to the astronomical Universe.  This course is for science majors or those with a strong interest in science.


In addition to learning about our Universe, a primary goal of this class is to develop scientific thinking and problem solving abilities.  Equations and numerical calculations will be a component of this class.   A working knowledge of algebra and geometry is essential for this class.  A knowledge of calculus, however, will not be required this semester.


The course website can be accessed from (  This page will contain links to course information, and copies of past homeworks and lecture notes.   


Course Structure


This course consists of two lectures and one discussion period per week.


The lectures will be on Tuesday and Thursday at 11.00am-12.15pm (room CSS2428) and will contain the bulk of the course material.  They will also provide a crucial forum for general questions and class discussion.  It is intended that the lectures parallel the text.  Thus, it is very important that you read the textbook.  You will gain maximum benefit from the textbook if you read the respective chapters before the corresponding class.  Some material that we discuss in class will, however, not be in the textbook.  Unless explicitly stated, all material presented in the class (whether in the textbook or not) is fair game for homework assignments and examinations.  You are expected to attend all lectures.


The discussion periods (Friday 1.00-1.50pm) play a variety of roles.  Primarily they provide an opportunity to think about and apply the lecture material.  These periods are also a forum for question-and-answer sessions, problem-solving practice, and group discussions of issues brought up in the lectures.  You are expected to attend the discussion section, and some fraction of your grade will depend on your attendance at this sessions.





Your final grade will be based on one midterm exam, in-class exercises, homeworks, discussion section worksheets, the night lab, and the final exam.  Grade will be given using a 700-point scale.   The breakdown of these points is as follows:


            100 points for first mid-term exam

            100 points for second mid-term exam

            150 points for homeworks

            100 points for discussion period attendance and worksheets

            50 points for project work

            200 points for final exam


Midterm exam : The two midterm exams are scheduled for the 1st October 2009 and the 3rd November 2009.  Each exam will cover all material presented in the lectures up to that date.  The exams will occur in the regularly scheduled class period (i.e., Tuesday 11.00am-12.15pm).  Notes and books will not be allowed in the exam, but you should bring your calculator.


Final Exam : The final exam is scheduled by the University for Monday 14th December 2009 at 8.00am-10.00am.   Again, notes, and books will not be allowed in this exam.


Missed Exams : The University recognizes only a few excuses for missing exams, including religious holidays, University-approved travel (including athletic-related travel), and personal or family illness.  If you know that you have to miss an exam for one of these valid reasons, you must inform me as soon as possible (and certainly before the exam itself).  If an emergency arises on the day of the exam, you must contact me as soon as possible after the exam.  In either case, we will schedule a make-up exam (which may be oral or written, at my discretion).  THE REASONS FOR MISSING AN EXAM MUST BE FULLY DOCUMENTED IN WRITING.   Furthermore, please note that any make-up exam for the final exam must be taken no later than 48 hours after the regularly scheduled final exam time.  This requirement is imposed by University policy.


Homework : There will be at least one homework every two weeks (and sometimes one homework per week).  Each homework will clearly have a stated due date.  It must be turned in at the beginning of class on the due date or else it will be considered late.  Late homework may be turned in up to 1 week after the due date for a 30% penalty.  After one week, the graded homeworks together with solution sets will be handed back; no late homework can be accepted after that time.


Finally, please note that the grading structure of the course makes it impossible to get a high grade unless you do well in the homeworks and the discussion section.  Simply doing well in the exams will not ensure that you get a good grade!


Academic Integrity


The University’s policies and rules on academic integrity are laid out in the Fall 2009 Schedule of Classes on Page 35.   In essence, you must never engage in acts of academic dishonesty at any time.   Acts of academic dishonest include cheating, fabrication, plagiarism, or helping any other person to do any of these things. These rules apply to homeworks and quizzes as well as exams.   As a part of these rules, you must give credit to any book (including the course textbook!), published article or web-page that you have used to help you with a particular assignment.   The University takes these issues extremely seriously, as do I.


To underscore the need for academic integrity, the University asks you to write the following pledge on any assignment or exam:


I pledge on my honor that I have not given or received any unauthorized assistance on this assignment/examination.”



Students with Special Needs


Students with a disability who wish to discuss academic accommodations should contact me as soon as possible.  In addition, if you haven’t done so already, you should contact the University’s Disability Support Service (DSS) at 301-314-7682.



Preliminary course outline


Date                 Lecture                                                                                    Chapter


1-September    Introduction; The scale of things                                             1



3-September    Ancient models of the Solar System                                       4

8                      The laws of planetary motion                                                  4

10                    Newtonian mechanics                                                             4

15                    Gravitational physics                                                               4

17                    Orbital mechanics and tides                                                     4

22                    Tides beyond the Earth-Moon system                         4

24                    Our view of the heavens: the Celestial sphere             2

29                    Celestial coordinates and navigation                                        2,3

1-October        MIDTERM EXAM 1



6-October        Electromagnetic radiation                                                        5

8                      Electromagnetic spectra and the structure of atoms                 5

13                    Modern telescopes                                                                  6

15                    Structure and patterns in our Solar System                             7

20                    The origin of our Solar System                                               8

22                    The Solar Systems: the exo-planet revolution             8

27                    The Earth as a planet                                                               9

29                    The properties and dynamics of the Moon                              10

3-November    MIDTERM EXAM 2

5                      The Terrestrial planets: interiors                                              11

10                    The Terrestrial planets: atmospheres                                       11

12                    The giant planets: Jupiter and Saturn                                       12

17                    The giant planets: Jupiter and Saturn                                       12

19                    Satellites of the giant planets                                                   13

24                    Outer solar system: Uranus, Neptune, and minor bodies        14

26                    THANKSGIVING

1-December     Interplanetary debris                                                                15



3-December     Properties and structure of the Sun                                         16

8                      Powering the Sun                                                                    16

10                    Life cycle of the Sun                                                               -


14-December  FINAL EXAM (8.00-10.00am; CSS2428)