ASTR 21The Diverse Universe: Stars, Planets, and Galaxies
Introductory course for students pursuing the astrophysics major (or who have a similar physics/math background). Course introduces students to current topics and research in a astronomy and astrophysics, and gives students the background necessary for success in the 100-level Astrophysics laboratory classes (PHYS 135 or ASTR 136). Class focuses on three central types of objects in modern astronomy: stars, planets, and galaxies, building off of our nearest examples, the Sun, solar system planets, and the Milky Way. The class differs from GE classes like ASTR 2 in that a higher level of math and physics experience is assumed.
Prerequisite(s): PHYS 5A or PHYS 15A.
Find a section and add it to your scheduleLive seat counts, time-conflict checks and the walk from your previous class.
When it runs
Winter 2027Open Winter 2027
| Section | Type | When | Where | Instructor | Seats |
|---|---|---|---|---|---|
| 01 | Lecture | Mon Wed Fri 1:20pm–2:25pm | Sci & Engr Library 206 | S. E. Sallum | Open 0/75 |
Spring 2026Open Spring 2026
| Section | Type | When | Where | Instructor | Seats |
|---|---|---|---|---|---|
| 01 | Lecture | Tue Thu 1:30pm–3:05pm | Earth&Marine B210 | G. H. Smith | Open 20/40 |
Winter 2026Open Winter 2026
| Section | Type | When | Where | Instructor | Seats |
|---|---|---|---|---|---|
| 01 | Lecture | Mon Wed Fri 1:20pm–2:25pm | PhysSciences 110 | J. J. Fortney, B. M. Gaensler | Open 34/50 |
Who teaches it
| Instructor | Rating | Difficulty | Would take again | Reviews |
|---|---|---|---|---|
| Graeme Smith | 4.4 / 5 | 2.2 / 5 | 94% | 37 |
| Jonathan Fortney | 3.7 / 5 | 3.4 / 5 | 67% | 8 |
From RateMyProfessors, which is student-submitted and not a survey. Small review counts move a long way on one bad quarter.
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