Astronomy 142 Elementary Astrophysics
Spring 2026

Lecture Date

Topic

Reading

Recitation

Stellar astrophysics: How stars work

Jan. 20 Approximations, scaling relations, characteristic scales, and averages
Jan. 22 Observations of stars Kutner Ch. 2
Ryden Sec. 5.7 & 13.1-13.4
No recitation this week!
Jan. 27 Binary stars Kutner Ch. 5
Ryden Sec. 13.5-13.6
Jan. 29 Stellar structure Kutner Ch. 9.4
Ryden Sec. 14.1, 15.1, 15.Appendix
Rec 1
Feb. 3 The Sun Kutner Ch. 6
Ryden Sec. 7.1-7.2 & 15.1.3-15.2
Feb. 5 Nuclear fusion Kutner Ch. 9.2-9.3
Ryden Sec. 15.3
Rec 2, Data table
Feb. 10 Stellar interiors Kutner Ch. 9.5-9.6
Ryden Sec. 15.4 & 17.3

Stellar evolution: How stars live their lives, and the corpses they leave behind

Feb. 12 Dead and failed stars Kutner Ch. 10.4 & 11.2-11.3
Ryden Sec. 18.1-18.2
Rec 3
Feb. 17 Stellar mass black holes Kutner Ch. 8.4 & 11.5
Ryden Sec. 18.3
Feb. 19 Normal stars and the main sequence Kutner Ch. 3.5 & 10.1
Ryden Sec. 14.4
Rec 4
Feb. 24 Star clusters and stellar evolution Kutner Ch. 3.2, 11.1, & 13
Ryden Sec. 14.2-14.3, 17.2, & 18.4
Feb. 26 Midterm #1 No recitation this week!

The interstellar medium: The reservoir of material from which stars form and to which they return material when they die

Mar. 3 Interstellar dust Kutner Ch. 14.2-14.3
Ryden Sec. 16.1
Mar. 5 Interstellar gas Kutner Ch. 3.1, 3.3-3.4, & 14.4-14.5
Ryden Ch. 5.1-5.3 & 16.2-16.3
Rec 5
Mar. 10 No class - Spring break!
Mar. 12 No class - Spring break! No recitation this week!
Mar. 17 Star formation Kutner Ch. 15
Ryden Sec. 17.1

Normal galaxies: Structure and dynamics

Mar. 19 The Milky Way: shape of the galaxy, stellar populations and motions, stars as a gas Kutner Ch. 16.4
Ryden Sec. 19.1-19.3
Rec 6
Hyades data, ZAMS data
Mar. 24 The Milky Way: stellar relaxation time, differential rotation of the disk, local standard of rest, and galactic rotation curves Kutner Ch. 16.2-16.3 & 16.5
Ryden Sec. 19.4-19.6
Mar. 26 Normal galaxies: the Hubble sequence Kutner Ch. 17.1-17.2
Ryden Sec. 20.1
Rec 7
Mar. 31 Normal galaxies: spectra Kutner Ch. 17.3-17.4
Ryden Sec. 20.2
Apr. 2 Distances to galaxies: standard candles and standard rulers Kutner 12.2, 18.1-18.3 & 20.5
Ryden Sec. 20.4
Rec 8
Cepheids (DDO)

Galaxy clusters and unusual galaxies

Apr. 7 The most distant galaxies: Hubble's Law, measurements of H0, and AGN Kutner Ch. 18.5-18.6 & 19.4
Ryden Sec. 20.5 & 21.2
Apr. 9 AGN Kutner Sec. 19.2-19.3, 19.6
Ryden Sec. 21.1, 21.3, & 21.Appendix
Rec 9
Apr. 14 Groups of galaxies Kutner Ch. 18.4, 19.1
Ryden Sec. 21.4-21.5 & Ch. 22
Apr. 16 Midterm #2 No recitation this week!

Cosmology: The structure and origin of the Universe

Apr. 21 The Big Bang Kutner Ch. 20.1-20.2 & 21.2
Ryden Sec. 23.1
Apr. 23 General Relativity and the Universe Kutner Ch. 20.4
Ryden Sec. 23.2-23.5
Rec 10
Apr. 28 Finding the Universe among the universes Kutner Ch. 21.4
Ryden Sec. 24.1-24.2
Apr. 30 Properties of our Universe since decoupling Kutner Ch. 21.1
Ryden Sec. 24.3-24.4
Rec 11
May 7 Final exam