Skip to main content

ASTR 201: Astronomy for Science Majors

A quantitative introduction to astrophysics — extracting physical insight from limited observations using mathematics and physics.

Course logistics

ASTR 201 is a 3-unit course required for the Astronomy pre-major. It meets twice weekly for in-person lectures; come ready to reason, not just listen.

CourseASTR 201 — Astronomy for Science Majors
TermSpring 2027 (PLACEHOLDER — confirm)
MeetingsTue & Thu, 12
–1
pm (PLACEHOLDER — confirm Sp27)
LocationLH 245 (PLACEHOLDER — confirm Sp27)
Units3
PrerequisitePhys 195 (intro mechanics); satisfaction of the SDSU Mathematics/Quantitative Reasoning Assessment

Required materials

Where things live

This is a quantitative course: we use math to build physical understanding and intuition, not rote memorization or plug-and-chug. You will practice interpreting equations, stating assumptions, and sanity-checking results (units, limits, scaling). As a required course for Astronomy pre-majors, ASTR 201 also prepares you for upper-division Physics and Astronomy coursework.

Course Objectives

Grading

Grade categories
CategoryWeight
Problem sets30%
Growth memos10%
Scholarly engagement10%
Midterm 115%
Midterm 215%
Final exam20%

Letter scale

Minimum percentage for each letter grade
GradeMinimum %
A93
A-90
B+87
B83
B-80
C+77
C73
C-70
D60
F0

Office Hours

DayTimeLocationModality
Friday11:0013:00Additional times available by appointment.Physics 239in-person

Contact

InstructorAnna Rosen
Responsewithin 24 hours
Asynccanvas-msgastr-201-canvas

Academic integrity

All submitted work in this course must reflect your own understanding. Collaboration is strongly encouraged for discussing concepts and strategies. However, what you submit must be written independently and must represent your unique reasoning. Copying solutions — from classmates, the internet, generative AI, or solution manuals — is not permitted. Violations are handled according to university procedures and may be reported to the Center for Student Rights and Responsibilities.

Generative AI policy

Do not use general-purpose AI tools to produce, rewrite, or “polish” anything you submit for a grade. Disclose AI use whenever a submission asks for AI/collaboration disclosure, even if the use was allowed. You are responsible for the correctness of your work and for being able to reproduce any reasoning you submit.

Allowed (study support):

Not allowed (graded work):

To support effective studying, the instructor provides course-specific tools grounded in course materials only (lecture notes, textbook, vetted sources), including a private ASTR 201 NotebookLM notebook.

Course materials

Lecture notes, slides, homework, and exams are the intellectual property of the instructor. You may use course materials for your own educational purposes in this course, but you may not reproduce, distribute, share, or post them on any public platform (e.g., Chegg, Course Hero, Discord servers, public GitHub repos) without written permission. Unauthorized recording or redistribution of class sessions or office hours is prohibited.

Attendance & classroom norms

We are all members of a professional academic community. Treat classmates and the instructor with respect; spirited, courteous debate about scientific ideas is welcome. Because active reasoning is the point of being in the room, phone and other non-course device use during class is not permitted. Formal attendance is not taken, but you cannot earn Scholarly Engagement credit if you are not present and participating. Please arrive on time.

Diversity & inclusivity

This classroom is a place where you will be treated with respect, and where individuals of all ages, backgrounds, beliefs, ethnicities, genders, gender identities, gender expressions, national origins, religious affiliations, sexual orientations, abilities, and other visible and non-visible differences are welcome. All members of this class are expected to contribute to a respectful, welcoming, and inclusive environment for every other member.

Land acknowledgement

San Diego State University sits on Kumeyaay land. The Kumeyaay people have lived in this region for over 10,000 years and continue to live here today.

Accessibility & Accommodations

DeadlineSubmit requests at least 2 weeks before an exam or graded activity.