Level and scope: The level of this web material targets 1st & 2nd year astronomy/astrophysics graduate students -- so, roughly an Annual Reviews (ARAA) article, but minus the detail. Senior undergraduates may also find parts useful, as well as more seasoned researchers who want to quickly review a subject outside their particular specialty. My aim has been to summarize our basic understanding of each sub-area of extragalactic astronomy, providing just enough background to follow the material, but consciously excluding many (albeit interesting) details, or fine points of current contention or, indeed, much historical background. These notes are therefore goal oriented -- the goal being a complete but concise accounting of our current knowledge of extragalactic astronomy.
Style: Reflecting my own background, the style of these notes leans more towards a conceptual approach than a mathematically rigorous one -- but I have tried to keep the physical principles to the fore, with enough mathematical/numerical content to put flesh on the bones when needed. As it happens, much of the subject has advanced along an observational/empirical path, so a physically rooted intuitive approach is, more often than not, both appropriate and sufficient.
Exclusions: Because our students take a number of other courses, I have not attempted to be thorough in areas of overlap, such as : basic physical processes encountered in the ISM & high energy astrophysics; stellar structure & evolution; observational techniques and instrumentation; radio astronomy; and the Milky Way Galaxy. Excluding these is in anycase necessary - even a cursory treatment of the various extragalactic sub-fields requires two semesters to complete, three if one gives stellar dynamics, cosmology and galaxy formation the time they deserve.
Breadth over Depth: There are two types of graduate course: core courses which give beginning students a broad exposure to one branch of astrophysics; and specialized courses which capitalize on faculty expertise to take senior students deeper into an area. This web material was developed for our core extragalactic courses, but I suspect it might also be a useful resource in more specialized courses.
It has been a hard couple of semesters creating this, but I've learned a great deal --- I hope you do too !
Topics not yet prepared include : 10 (populations), 17-20 (galaxy formation; the IGM; large scale structure; dark matter; gravitational lensing), and there are still gaps in some of the other topics (9, 13-15). The homework questions, references, and figures have also been slow to develop, though there is now a skeletal presence for most topics. Of course, if you find errors, omissions, or confusions, etc, I would very much appreciate you letting me know, and I will try to rectify them. Similarly, if you find I have lifted a figure or text from your own web material, and have not acknowledged it properly -- I'm sorry ! -- it was not intentional, but probably arose from desparately trying to complete the notes before I taught the class. Let me know and I'll include the acknowledgement or remove the figure or text if that is what you prefer. Finally, if you have better or additional figures that you would like to add, please let me know so I can include them.
Hopefully, in time, the content and style of the course will improve
and mature. My intention is to provide a powerful resource, primarily
for all those studying or teaching in graduate astronomy research
programs. My secondary target audience are all those of us who, once
leaving graduate school, were either too focussed or too busy to keep
pace with all the developments in extragalactic astronomy. I know I've
learned and/or clarified a great deal preparing these notes, so unless I
started out unusually ignorant, it is likely that others in my position
may also find them to be of value.
With good wishes, Mark Whittle.
(email : dmw8f@virginia.edu)