Physics 443/543 and Astro 443 --
Galaxies and the Milky Way
Professor: rachel somerville
Hubble Ultra Deep Field;
Hubble Heritage image M66; Coma cluster
1. Overview and Course Description
Galaxies are an important nexus in the cosmic hierarchy: they serve
as lighthouses marking out the vast cosmic structures that can span
many millions of parsecs, but are fascinating in themselves as
laboratories for the "small scale" processes of stellar birth and
evolution. We now have images of billions of galaxies, and can
observe them from a time less than a billion years after the Big
Bang until the present day. We can study not only the appearance or
"morphology" of galaxies, but also in some cases measure properties
of their stellar populations, their quota of heavy elements, their
gas content, and the internal motions (or kinematics) of their stars
and gas. Although galaxies exhibit amazing diversity, they also
conform to certain surprisingly tight correlations. From kinematic
measurements, we can infer that galaxies contain a major unseen
component that influences the motions of their stars and gas: the
mysterious "dark matter". Moreover, the stars and gas that we can
measure within galaxies falls far short of what we would expect for
the cosmic "baryon budget". The study of modern galaxy formation
focuses on trying to understand the observed demographics and
correlations of galaxy properties and how these evolve over cosmic
time, in the context of the "hierarchical structure formation"
picture provided by the Cold Dark Matter theory.
In this course, we will warm up with a brief review of stars and
radiative processes and basic cosmology. We will start our study of
galaxies with our home Galaxy, the Milky Way, our sister galaxy M31
(Andromeda), and our smaller companions the Local Group dwarfs. Even
this relatively small population of galaxies in our own "backyard"
poses a number of unsolved puzzles. We will then cover the
properties of spiral, lenticular, and elliptical galaxies in the
'nearby' Universe, and discuss the larger structures that form
galaxy habitats: groups and clusters. One fascinating open question
is whether galaxy properties are mainly shaped by "internal"
processes or by their environment. We will discuss the evidence that
many or even most galaxies harbor supermassive black holes in their
nuclei. We will wind up the course with a discussion of how we can
find and observe extremely distant (high redshift) galaxies, and of
how galaxies were different in the past.
2. Instructor and Venue
Prof. rachel somerville
email: somerville [at] physics.rutgers.edu
office: 317 Serin
office hours by appointment
The course is scheduled for MTh in Serin 401
3. Class Format and Grading
The course will be run as a lecture/discussion, and in order for
this to work well, it is imperative that students complete the
assigned reading before class. Grades will be based on
class attendance and participation, approximately 5 homework
assignments, in-class quizzes, and a final paper and presentation.
Sakai will be used to distribute and collect homework assignments.
The main text for the course is Extragalactic
Astronomy and Cosmology, Second Edition, by Peter Schneider.
It should be available in the bookstore. Make sure you get the
Several other textbooks that may be useful for supplemental
Galaxies in the Universe (Second Edition), by L.S. Sparke
and J.S. Gallagher: classic undergraduate level textbook on
Galaxy Formation and Evolution by Mo, van den Bosch &
White: a recent and comprehensive graduate level textbook.
Introduction to Cosmology by Ryden: very useful and clear
text if you need to brush up on your cosmology
An Introduction to Modern Astrophysics by Caroll &
Ostlie: useful basic reference
5. Students with Disabilities
If you have a disability, please contact Professor Somerville
early in the semester to make the necessary arrangements to ensure
a successful learning experience.
here for more information.
6. Useful links:
Astrophysics Data System (ADS)
Wright's Cosmology Tutorial (and News)