Astronomy 406: Fall 2020

Stellar Structure and Evolution

Star forming molecular clod: gas density (He, Ricotti, & Geen 2019) 

The goal of this course is to give students a “physical understanding” of stellar structure, star formation and evolution. We will try to explain basic concepts in simple, sometimes intuitive, physical terms. In the lectures, we will cover many topics about stars in general (not on “solar physics”), including:

This course is designed for Astronomy and Physics majors. You must have completed ASTR320 (Theoretical Astrophysics) or obtained permission from the Astronomy Department.


    Instructor:  		Massimo Ricotti
    Class:       		ATL 2324
    Lectures:    		Tuesday and Thursday from 12:30pm to 13:45pm
    First class: 		Tue Sep 1 
    Last  class: 		Thu Dec 10 

What's New?

Sep 1: First class on zoom (check ELMS)

Contact info and Notes

Course Outline

The Syllabus is available on ELMS and here PDF format.


Basic Principles
#1Sep 1 Course Introduction; observations of stellar parameters, H-R diagram
#2Sep 3 Hydrostatic equilibrium and virial theorem
#3Sep 8 Gas physics: EOS
#4Sep 10 Opacities in stars
#5Sep 15 Radiative transport
#6Sep 17 Convective transport
#7Sep 22 Nuclear fusion; the s- and r-processes
#8Sep 24 Summary: stellar timescales
#9Sep 29 Equations of stellar structure, polytrophs, Lane-Emden equation
#10Oct 1 Calculating stellar evolution, the MESA code
Star Formation and Stellar Evolution
#11Oct 8 Star formation
#12 Oct 15 The main sequence
#13Oct 20 Post main sequence evolution
#14Oct 22 Stellar winds mass loss
#15Oct 27 Red giant phase
#16Oct 29 Horizontal branch stars
#17Nov 3 Asymptotic giant branch stars
Late evolution and stellar remnants
#18Nov 5 Post-AGB and Planetary nebulae
#19Nov 10 White dwarfs and neutron stars
#20Nov 12 Pulsating stars
#21Nov 17 Observational evidence of mass loss
#22Nov 19 Evolution of massive stars 8-25 Msun
#23Nov 24 Evolution of massive stars >25 Msun
- Nov 26 THANKSGIVING (no class)
#24Dec 1 Supernovae
#25Dec 3 Close binaries and mass transfer (X-ray binaries, novae, CVs)
#26Dec 8 Chemical yields
#27Dec 10 Review session
-Dec 21 FINAL EXAM (official date/time: 1:30pm-3:30pm; format and time TBD)


Required textbook:
  • Understanding Stellar Evolution by Lamers & Levesque
    IOP Astronomy ebook [must log-in from UMd network to get free access]
This is a free book available in pdf, ePub and Kindle formats. Slides and exercises are also available from the same publisher. I will rely mainly on this ebook and the accompanying slides in addition to other material, mainly from Max Pettini’s lectures at IoA Cambridge (that I will make available on ELMS).

Course Grading

  • Class participation/Quizzes 15%
  • Homework 35%
  • Midterm exam 25%
  • Final exam 25%
Letter grades will be assigned guided by the following scheme.
  • A 100% - 90%
  • B 89.9% - 80%
  • C 79.9% - 70%
  • D 69.9% - 60%
  • F below 60%
I will also adopt the finer division of the letter grades using pluses and minuses.


Homework will be assigned approximately every other week (total of 5 homework). Their due dates will be announced at the time they are assigned. On the due date the students will be expected to upload the HW on ELMS. The homework turned in will be graded and returned to the students. I will provide solutions and discuss them in class.

I will post the HOMEWORK and solutions on ELMS

Wiki pages related to class's discussions

Class #1