Spring 2025 Wednesdays 2:30pm-3:30pm
Jonathan Williams and Istvan Szapudi, Institute for Astronomy
Estimation is an essential skill for astronomy and life in general. This course will introduce students to the utility of order of magnitude calculations and practicing the ability to "think on your feet". I will give short overviews of basic physical concepts but the majority of the class time will be spent interactively, with students tackling problems at the whiteboard. I will give a list of questions, some based on recent colloquia, and the homework is to prepare for one of them each week. Problem sets will be pre-assigned with questions similar (and sometimes identical) to some in the If time permits, I will challenge the class by extending the problem or asking a new, unseen question.
Grading is based mainly on participation. Showing up and being ready to answer the pre-assigned questions will account for 80% of the grade. If you cannot attend class because of a good reason (i.e., not because of a pressing deadline for something else), please let me know in advance. Students will submit their own order-of-magnitude astrophysics question and answer for the remaining 20% of the grade.
Introduction to the course -- the one and only lecture to be posted. Cheatsheet of useful constants and conversion factors .
Related courses and (optional) reading:
- Astrophysics in a Nutshell by Dan Maoz for a good introduction to the various astrophysical concepts we will be using
- Eugene Chiang's Order of Magnitude Physics course (Berkeley)
- Sterl Phinney's Order of Magnitude Physics course (Caltech)
- A long list of questions (Ohio State).
- Dave Jewitt's Order of Magnitude Earth and Planetary Sciences course (UCLA)
- Order-of-Magnitude Physics: Understanding the World with Dimensional Analysis, Educated Guesswork, and White Lies (Goldreich, Mahajan, & Phinney)
- The Astronomical Reach of Fundamental Physics (Burrows & Ostriker 2014)