# Which astronomy course should you take?

We know this can be a confusing problem, so we will try to explain the
intended audience for our three introductory sequences and for our two
upper-division astrophysics courses. This is the "plain English"
description of these courses: see the OSU "Course Offerings Bulletin"
for definitive language, and consult your adviser if you have any
questions about how these courses fit into your curriculum.

## Introductory Non-Majors Courses

The Astronomy Department offers 5 introductory-level courses for non-majors
that satisfy the GEC physical sciences requirement:

**Astronomy 161:** Introduction to Solar System Astronomy (5 cr)
**Astronomy 162:** Introduction to Stellar, Galactic, &
Extragalactic Astronomy (5 cr)
**Astronomy 141:** Life in the Universe (5 cr)
**Astronomy 142:** Black Holes (5 cr)
**Astronomy 143:** History of the Universe (5 cr)

The first two (Astronomy 161 & 162) are a 2-quarter sequence, though
many students also take just Astronomy 161 as a non-sequence GEC
physical sciences course. Astronomy 141-143 are individual courses (but
not a sequence) that satisify the single-quarter GEC physical sciences
course requirment.

### Astronomy 161-162

This is our 2-quarter introductory astronomy sequence, usually taken by
students to meet the science component of the General Education
Curriculum (GEC) or as a free elective. The mathematics used in this
course is minimal, nothing more complicated than simple algebra and
trigonometry. There is no formal laboratory, but there are
opportunities to enjoy planetarium demonstrations and to look through
telescopes (for which some instructors offer class credit).
Examinations are usually multiple choice, although some instructors use
other test formats (such as short written answers to questions). The
course format is 5 hours of lecture per week. Solar-system astronomy
and basic astronomical concepts (light and its interaction with matter,
gravity and orbits) are covered in Astronomy 161; stars, galaxies, and
the structure and evolution of the Universe are covered in Astronomy
162. Astronomy 161 can be taken alone, it is a prerequisite for
Astronomy 162. Each year we also offer

**Honors Sections** of this
sequence during the Autumn and Winter quarters. The honors sections are
smaller (30 students or fewer) and highly interactive, and are directed
primarily towards students who are not physical-science majors.

### Astronomy 141-143

These are single-quarter courses devoted to particular current topics in
modern Astronomy:

- Ast141: Life in the Universe
- Ast142: Black Holes
- Ast143: History of the Universe

All are 5-hour courses that are taught at the same basic level as
Astronomy 161 and 162 and may be taken in any order;

**they are not a
sequence**. They have similar prerequisites to Astronomy 161, and are
intended for those students who only need 1 quarter of a Physical
Sciences GEC and are interested in taking something other than our
Astronomy 161/162 sequence. They may also be taken as electives.

## Introductory Astronomy Majors Courses

The introductory courses for Astronomy Majors and Minors are as follows:

*Astronomy 291: Basic Astrophysics & Planetary Astronomy*
(5 cr)

*Astronomy 292: Stellar, Galactic, & Extragalactic
Astronomy & Astrophysics* (5 cr)

*Astronomy 294: Introductory Seminar* (1 cr)

*Astronomy 350: Methods of Astronomical Observation & Data
Analysis* (5 cr)

### Astronomy 291-292: Introductory Astrophysics Sequence

This is a general survey of astrophysics, but unlike the 100-level
sequences, this course is intended

*primarily* for physical
sciences majors (including Astronomy majors and minors, for whom these
are required courses);

**it is not a GEC course**. These courses
assume that students have already had (and passed) a year of
college-level calculus (through Math 153 or equivalent) and at least one
year of classical physics, either completion of or concurrent
registration in Physics 133 or equivalent.

### Astronomy 294: Introductory Seminar

This is a 1-credit course taught during Autumn and Winter quarters. It
consists of a single session once per week with each of the Astronomy
faculty to introduce those considering becoming Astronomy Majors or
Minors with current research topics in the department. Normally taken
by Freshman or Sophomores, but open to anyone interested in changing
majors to Astronomy.

### Astronomy 350: Methods of Observational Astronomy & Data Analysis

Unlike the 100- and 200-level courses listed above, this is a course
designed primarily for Astronomy majors and minors, or for very
technically inclined Bachelors of Science students. Astronomy 350
concentrates on the statistical treatment of experimental data as
applied to astronomical problems of the detection of photons. Although
specific to observational astronomy, the statistical methods developed
in this course are generally applicable to any of the physical sciences
or engineering. Prerequisites include Astronomy 292 (or Astronomy 162
in

*very exceptional cases*), Math 153, and Physics 133.
Interested students who are not Astronomy majors/minors and/or who have
not taken the Astronomy 291/292 sequence must speak with the instructor
before enrolling in this course.

## Upper Division (600-Level) Courses

In addition to the introductory sequences, there are two 600-level
Astronomy courses that do not have Astronomy prerequisites. These are
no-nonsense astrophysics courses that are intended primarily for
Astronomy majors/minors, as well as for Physics majors/minors or
graduate students in Physics (note that these courses are cross-listed
in Physics). Astronomy majors are required to take at least

*one* of these courses, but may (and are encouraged to) take the
other as a free elective. These courses are taught in Winter Quarter in
alternate years. Prerequisites for both courses are differential
equations (Math 255 or 415 or equivalent) and basic quantum physics
(Physics 253 or equivalent); completion of or concurrent registration in
statistical physics (Physics 621 or equivalent) is also recommended, but
not required.

### Astronomy 681/Physics 681:

Principles of Stellar Evolution & Nucleosynthesis.

This course provides an in-depth exploration of the structure and
evolution of stars, including nucleosynthesis in stellar interiors and
in supernova explosions. The equations of stellar structure are derived
from first physical principles, and the case of degenerate objects is
also treated. Topics covered in detail include radiation transport
mechanisms, nuclear reactions, and stellar evolution. This course is
offered in

*even-numbered* years.

### Astronomy 682/Physics 682:

Introduction to Cosmology.

This course provides a comprehensive introduction to standard Big-Bang
cosmology, including an introduction to the General Theory of
Relativity. Solutions to Einstein's equations are derived. The
structure and evolution of the Universe is studied through the Friedmann
equations, including the possible role of the cosmological constant. The
early thermal history of the Universe, including primordial particle
physics, nucleosynthesis, and the cosmic background radiation, are
explored in detail. The very early Universe, including inflation and
quantum cosmology and the origin of density fluctuations, is discussed
and observational tests of cosmological models are described. This
course is offered in

*odd-numbered* years.