Astro 3
The Nature of the Universe
Fall 2026
Introduction
This course provides a broad introduction to astronomy and our
place in the universe. We will start by discussing the mind-bogglingly
vast range in physical scales spanned by astronomy,
and then learn how we can perform astronomical observations
in our everyday lives.
We will then follow the history of astronomy as a science,
reviewing the fundamental physical concepts of motion,
energy, gravity, and light on which it
is based, along with the tools used to make astronomical measurements.
After these preliminaries, we will delve into the nature of
planets, stars, galaxies, and the Universe as a whole. At the
end of this course, students should appreciate the beauty
and power of the scientific method as it applies to astronomy.
Course Information
Professor:
Alice Shapley
aes@astro.ucla.edu
Phone: 206-3768
Office: 3-931 PAB
Office Hours: Friday 12:00-1:00 pm
TAs:
Lectures:
Monday, Wednesday, Friday, 11:00 am - 11:50 am, Physics and Astronomy (PAB) 1425
Discussion Sections (all in Knudsen 1116):
2B Tuesday 10:00 am - 11:50 am; TA: Nathan Magari
2C Tuesday 12:00 pm - 1:50 pm; TA: Elm Zweig
2D Wednesday 8:00 am - 9:50 am; TA: Nathan Magari
2E Thursday 10:00 am - 11:50 am; TA: Neel Nagarajan
2F Thursday 12:00 pm - 1:50 pm; TA: Neel Nagarajan
Textbook, etc.:
The Essential Cosmic Perspective (9th Edition, 2022) by Bennett, Donahue, Schneider, Voit (required). The textbook may be purchased new, used, or in digital form. See more information in the syllabus regarding the UCLA Bruin One Access program.
Astro 3 Lab Manual: Package of Lab exercises for discussion
sections (posted on BruinLearn, week by week).
A simple calculator is HIGHLY recommended, though not required.
Grading:
- Lab Assignments
20%: Weekly required assignments completed during 2-hour discussion section.
- Homework
10%: Weekly free-response questions based on lectures and reading (requiring one 100-word response per week).
- First Midterm
20%: Multiple-choice in-class exam (October 21st).
- Second Midterm
20%: Multiple-choice in-class exam (November 13th).
- Final Exam
30%: Primarily multiple-choice exam (December 7th).
Lab assignments are required. You must attend lab starting week 1 of the quarter. There will be no labs during weeks 7 and 9, due to the Veterans Day and Thanksgiving holidays. Labs for the course will be performed in the lab classroom (Knudsen 1116) during the 2-hour discussion section, and are to be handed in at the conclusion of the discussion section. Each lab assignment is roughly 10 pages in length and covers one of the key topics of the course in considerable depth through both hands-on activities and mathematical calculations. Attendance is required for labs. Your best 6 lab grades will be used to calculate your lab grade. This grading policy allows for missed labs due to extenuating circumstances. You must complete at least 5 labs in order to receive a passing grade in Astronomy 3. Exams may draw from topics covered during lab sessions.
Homework will be assigned roughly every week (starting week 1) and will consist of a 100-word response to a question that is based lectures and reading. Students must write their responses by hand on paper, scan, and upload to BruinLearn. In addition, there are weekly reading assignments from the textbook. Written homework responses will be due at 11:59 pm on each Monday, unless otherwise announced. No late homework will be accepted. At least 5 homework assignments must be turned in to pass the course. No generative AI is to be used
for these assignments.
Exams will consist of two midterms in class, each worth 20%, and a final exam worth 30%. The first midterm will take place on Wednesday, October 21st, and the second one on Friday, November 13th. The final exam will be on Monday, December 7th, from 11:30 am - 2:30 pm. The exams will be (almost) exclusively based on multiple choice questions.
Extra Credit opportunities will be announced during the quarter.
Learning Outcomes:
Based on lectures, hands-on laboratory exercises, and weekly homework quizzes, students will engage in the scientific process of inquiry, analysis, problem-solving, and quantitative reasoning. They will also acquire an informed appreciation of scientists, scientific research, and technology, make evidence-based decisions, discuss the interactions between humans and their physical world, and explain the origin and physical processes governing the Earth and the surrounding universe.
GE Credit Acknowledgement:
Upon successful completion of this course, students will satisfy the General Education requirement in the area of Foundations of Scientific Inquiry: Physical Sciences, including a laboratory/demo component. The laboratory component is fulfilled through 8 2-hour in-class laboratory assignments.
Prerequisites:
We will review all the basic physical concepts required for understanding the material in the course. However, we expect a knowledge of entry-level UC mathematics (algebra, geometry, and basic trigonometry).
Course Website: