Concepts of Astrophysics I

Astronomy 421 (Fall 2022) is intended for advanced (senior level) undergraduates, and is also counted as an elective for graduate students. This course covers the structure and evolution of stars, starting off with some basic physics including mechanics, radiation, atomic structure and relativity. We will then concentrate on stars for most of the remainder of the semester, examining their atmospheres, their interiors, stellar evolution, and stellar remnants (including black holes). In Astronomy 422 we will examine the properties of the interstellar medium, galaxies, large scale structure, and cosmology. A major emphasis of the course will be to instruct you on how to think (and write) like a scientist. We will have an exercise in peer review and a term paper. You will also present your research topic to the class. There will be no final exam.

Instructor: Prof. Greg Taylor, PAIS room 3236, email
Time and place: Tu/Th 9:30 AM-10:45 AM
PAIS 1160
Syllabus and course web page:
Lectures in PDF format:
Textbook: An Introduction to Modern Astrophysics, B.W. Carroll & D.A. Ostlie, 2nd Edition.
Prerequisites: Physics 330 or 491, 492 or their equivalent.
Exams and Grades: Your final grade will be determined through three sectional exams (each 20% of the grade), eight sets of homework (20%) and a term paper (20%). There will be no final exam.

Some useful links:
Science Daily's website for astronomy news
Greg Taylor's home page
Search engines for articles: ADS database,   Astro-ph
Example of term paper outline and final write-up. The outline and paper will of course be different depending on your topic, but by writing an outline we will be able to make sure that you work on the relevant pieces from the beginning. And you should study the example to see what all the parts are and the level of detail desired.

Code for statstar.f in fortran from Carrol & Ostlie

Code for in python2 courtesy Prof. D. Schiminovich

Code for in python3 courtesy Tousif Reza

Accommodations: UNM is committed to providing courses that are inclusive and accessible for all participants. As your instructor, it is my objective to facilitate an accessible classroom setting, in which students have full access and opportunity. If you are experiencing physical or academic barriers, or concerns related to mental health, physical health and/or COVID-19, please consult with me after class, via email/phone or during office/check-in hours (I am not legally permitted to inquire about the need for accommodations). We can meet your needs in collaboration with the Accessibility Resource Center ( at or by phone (505) 277-3506.

This is a three credit-hour course. Class meets for two 65-minute sessions of direct instruction for fifteen weeks during the Fall 2022 semester. Please plan for a minimum of six hours of out-of-class work (or homework, study, assignment completion, and class preparation) each week.

Our classroom and our university should always be spaces of mutual respect, kindness, and support, without fear of discrimination, harassment, or violence. Should you ever need assistance or have concerns about incidents that violate this principle, please access the resources available to you on campus. Please note that, because UNM faculty, TAs, and GAs are considered "responsible employees" by the Department of Education, any disclosure of gender discrimination (including sexual harassment, sexual misconduct, and sexual violence) made to a faculty member, TA, or GA must be reported by that faculty member, TA, or GA to the university's Title IX coordinator. For more information on the campus policy regarding sexual misconduct, please see:

Lecture schedule - updated 6/10/22

Date Topic Chapter
Tu Aug 23 Course Introduction, Mechanics I 1,2
Th Aug 25 Mechanics II 2, 19.2
Tu Aug 30 Radiation and Matter I 3
Th Sep 1 Radiation and Matter II
Homework 1 due
Tu Sep 6 Special Relativity I
Term paper topics due
Th Sep 8 Special Relativity II
Homework 2 due
4, 17.2
Tu Sep 13 Binary Stars
Th Sep 15 Spectral Lines
Homework 3 due
3, 8
Tu Sep 20 Review 2, 3, 4, 5, 7, 8
Th Sep 22 Exam 1 2, 3, 4, 5, 7, 8
Tu Sep 27 Telescopes 6
Th Sep 29 Stellar Atmospheres I
Tu Oct 4 Stellar Atmospheres II
Th Oct 6 Stellar Atmospheres III
Homework 4 due
Tu Oct 11 Stellar Interiors I
Term paper outline due
Th Oct 13 Fall Break
Tu Oct 18 Stellar Interiors II 10
Th Oct 20 Stellar Evolution I
Homework 5 due
Tu Oct 25 Review
6, 8, 9, 10
Th Oct 27 Exam 2 6, 8, 9, 10
Tu Nov 1 Stellar Evolution II
Th Nov 3 Stellar Evolution III
13, 15
Tu Nov 8 Stellar Remnants: White Dwarfs
Homework 6 due
Th Nov 10 Stellar Remnants: Black Holes
Tu Nov 15 Stellar Explosions: GRBs and Magnetars
Homework 7 due
Th Nov 17 Finish GRBs and Magnetars and Review 16
Tu Nov 22 Exam 3 10, 13, 15, 16, 17
Th Nov 24 Thanksgiving
Tu Nov 29 Peer Review Exercise
Homework 8 written reports due on Nov 28 at noon
Th Dec 1 Stellar Remnants: Neutron Stars
Tu Dec 6 Term paper presentations: 1-7
Th Dec 8 Term paper presentations: 8-14
Mo Dec 12 Written papers Due by 12:00pm MDT