Principles of Astronomy

Astronomy 101:  Principles of Astronomy

About the Instructor

Douglas Leonard, San Diego State University.

I believe it’s crucial to provide a variety of ways for students in an introductory course to access the course material -- some students learn best aurally and respond well to material delivered by lectures, while others learn most effectively from a book.  It is thus very important that my course provide an excellent, self-contained text whose content mirrors what is presented in class.  The choice of text is therefore one I don’t take lightly!

Students are typically first and second year undergraduates with a wide range of majors (including undeclared), taking a science course in order to fulfill a General Education requirement.  Occasional Juniors and Seniors also take the course out of interest.  There are no college-level pre-requisites; knowledge of high-school level algebra and geometry is assumed.

OER Adoption Process

1.  Briefly describe what motivated you to adopt OER for this 

2. How did you find and select OER for this course?

My path was a bit unusual.  When I started teaching Astronomy 101 in 2006, I thoroughly reviewed over a dozen introductory astronomy textbooks and selected as the best one  “Voyages Through the Universe”, by Fraknoi, Morrison & Wolff.  I happily used this text for the next 10 years. Thus, I was delighted when the same authors created the “Astronomy” textbook through OpenStax; upon reviewing it I found it to be of the same high quality as the one I had chosen years earlier, but with this one available completely free to the student.  (It is also available as an optional print-on-demand text through my campus bookstore for those students who still desire a printed version – several still do each semester.  Even this service, though, provides a cheaper printed text than the older version.) Finally, OpenStax encourages adopters to adapt the book as they wish to best suit the needs of their course.  This has allowed me to create a customized version of the text that now even more closely mirrors the content delivered by my lectures.

3. Describe any challenges you experienced and how you resolved them.

I can’t really think of any particular institutional “challenges”:  My Bookstore worked with me to provide the optional printed edition, and my department and campus fully supported my adoption of the online text.  Students also have been grateful for the cost savings. My main concern was that students might not read the text as often or as thoroughly if it wasn’t printed; this was balanced by the idea that they would have increased access to it since it was digital and available to them at any time.  

Course Description

Provide a brief course description with title, course number, and classification as a General Education Course or a Major Course. If possible, include any prerequisites courses.

Astronomy 101:  Principles of Astronomy.  General Education Course.

Official Catalog Description:  Discover the universe: planets, stars, galaxies, and our place in the cosmos; the Big Bang; how stars shine; comets, meteors, nebulae, the Milky Way; black holes and other exotic objects.

My expanded description: Finding our place in the universe has been a perennial human pastime.  Here we present the results of this ongoing endeavor, covering such topics as the solar system, stars, black holes, galaxies, and cosmology.  A particular emphasis will be placed on the historical development of ideas and their philosophical implications.  The class assumes no prior background in astronomy, although a general knowledge of science at the high-school level will be helpful.  Mathematics will be limited to algebra and geometry.

Also, include list of student learning outcomes or expectations for the course.

Student Learning Outcomes:  

Upon completing this course, you should be able to:

  • Describe the physical location of the Earth with respect to the other constituents of the observable universe, and articulate the process by which humans attained this understanding;
  • Convince a fellow student who has never taken an astronomy class that it is possible to determine the chemical constituents of a star without ever visiting it, through the careful analysis of its light;
  • Explain the process by which stars, like our sun, produce energy during their lives, and how and why they ultimately die;
  • Present the currently favored scientific theory for what the ultimate fate of our universe will be, and outline the astronomical observations upon which the theory is based;
  • Describe at least three major areas in which our astronomical knowledge is known to be incomplete;
  • Read and comprehend articles concerning astronomy that appear in the popular press, and participate in discussions about them.

Curricular Changes and Student Access

1. What did you change as part of the OER adoption?

I thoroughly revised my course syllabus and reading assignments to directly correlate my lectures to the material delivered by the textbook. I now provide students with a “Course Reader” that maps out – week by week – the text’s reading with what is being presented by the lectures.  

2. How and where do students access materials?

Students access the digital textbook primarily through a direct download at a link provided in the Course’s Blackboard web page.  Students who desire a print edition can purchase this at the campus bookstore through print-on-demand; the cost is less than a standard text.

Teaching and Learning Impact

Describe effects on teaching and learning that resulted from adopting OER e.g.

  • Do you collaborate more with other faculty now or use a broader range of teaching materials and methodologies, etc.?
  • Have student grades improved or stayed the same? N
  • Did student retention improve?
  • Did you experience any unintended results? What were they?

Consider attaching a file/link of any formal assessments e.g. survey results, impact reports, etc.

Student performance in my class has, on the whole, remained the same following adoption of the OER text:  The mean course GPA has been essentially unchanged.  I did a quantitative test one semester by giving the same final exam I’d given students taking the course with the traditional textbook a few years earlier; the mean score was statistically identical to the earlier course offering’s.  

I have not noticed any changes in student retention; I do not find myself collaborating any differently with other faculty due to adoption of an OER text.  There have not been any negative, unintended results of adoption the OER text. 

One POSITIVE result that had not really occurred to me has been that OER is vastly more “accessible” than a traditional text for students with vision impairment: It already exists in digital format (capable of being read by screen readers), and the OpenStax Astronomy text comes with “alternate text” for all figures in the book:  Additional caption material specifically designed with the sight-impaired reader in mind that describes precisely what is shown visually by the figure.  I have now had a blind student perform exceptionally well in my course, thanks in part to the accessibility of the OER text.

Student Feedback or Participation

Please describe what students say or how they responded to OER usage.

Consider including links to any student-generated OER or feedback survey data.

Regrettably, my only responses from students are anecdotal, but they have been uniformly positive.  I have not formally polled them on their experience with the OER text.

Cost Savings

I regularly instruct of order 500 students per year.  The old text I was using sold for a retail of $80; used or rental is was around $40.  If I estimate an average of $50 per student, this comes to roughly a $25,000 overall cost savings to the student population in my course per year, or ~$75,000 overall.

Accessibility, Affordability, and Diversity

Consider providing as much feedback as you feel comfortable with.  

  • Are the technologies used readily available and affordable for students?
  • Do the pedagogical strategies support learners with diverse cultural, ethnic, and gender backgrounds?

As already mentioned, the digital version of the text has been extremely helpful for students with vision impairment.  

Sharing Best Practices

I have shared my OER experience with faculty and staff at my home
institution through presentations at their “SDSU Affordable Learning
$olutions Open Educational Resources Lunch and Learn” series. I was
also interviewed for the "2020 Textbook Affordability Conference” ( ) that was hosted (virtually, due to the pandemic)
by my university in Spring 2020, and the video of my interview is now
posted online at: