Homepage for Extragalactic Astronomy (Spring 2020)

Instructor: Donghui Jeong


Class descriptions

This course will introduce the key observational facts and theoretical ideas through which we understand the extragalactic Universe, everything beyond our own galactic home: the Milky Way. Galaxies are the basic building blocks of the large-scale structure of the Universe and a galaxy is a large cluster of stars, gas and dark matter that is held together by gravity. Throughout the course, we shall study the observational properties as well as the formation and evolution of galaxies including their stellar, interstellar, black hole and Dark Matter components. Properties of clusters of galaxies, intergalactic medium, cosmic background radiations will also be discussed.


ASTRO 501 (Fundamental Astronomy) and ASTRO 502 (Fundamental Astrophysics), or equivalent level of knowledge, is required. That is, I will assume that you are familiar with basic concepts and equations of radiative transfer, quantum mechanics, and gravitational dynamics. No prior knowledge about the general theory of relativity is required, and a necessary part of relativity will be covered in the class.


There is NO final exam, and your grades will be based on:

Seminar discussion
On Fridays, we will have a seminar discussion on a recent paper relevant to the course material. Each student is required to lead one discussion (because we will have 10 seminars with 10 students!) during the semester and to participate fully in all seminar discussions throughout the semester. The discussion leader will provide a necessary context for understanding the paper (which may require additional reading), briefly summarize the content, and get the ball rolling on the discussion. All other students will come prepared with comments and questions to contribute to the discussion. Preparation includes completing a "reading memo" and emailing it to the discussion leader and the instructor by 7 a.m. the day before the discussion. Reading memo evaluations are included in the 10% discussion contributions listed above (1 point each). See this document for the instruction.

The lowest homework score will be dropped for the final grade, and the letter grades will be given as following:
A (85-100), B (75-84), C (60-74), D (50-59).
Anyone below 50 will fail the class.


There are two textbooks that will be useful for this course. Both books are reserved and available for 2 hour checkout in the 2nd floor library in Davey.

Galaxy Formation and Evolution (Mo, van den Bosch, White) (QB857.M63 2010)
A comprehensive collection of essentially everything in the modern extragalactic astronomy and cosmology from inflation to galaxy formation. Chapters discussing the galaxy formation are particularly useful.

Extragalactic Astronomy and Cosmology (Schneider) (QB857.5.E96S38 2015)
This book covers many essential topics in a less technical level. Available though Penn State library as an ebook: read online.

Following two books are classic books in the field, and I studied them in the grad school. So, you may find them useful. The second edition of Galactic Dynamics is out in 2008, and I find it quite useful.
Galactic Dynamics (Binney and Tremaine)
Galactic Astronomy (Binney and Merrifield)

Syllabus and Reading Assignments

Friday seminar schedule

2/7 Alexander Belles Parikh et al, SDSS-IV MaNGA: the spatially resolved stellar initial mass function in ~400 early-type galaxies, MNRAS (2018) 477, 3954 - 3982
2/17 Stephen Kerby, Malinda Baer Lelli et al., One Law to Rule Them All: The Radial Acceleration Relation of Galaxies, ApJ (2017) 836, 152 (23pp)
(see also) Pengfei et al., Fitting the radial acceleration relation to individual SPARC galaxies, A&A (2018) 615, 3
2/21 Joseph Colosimo Marsh & Niemeyer, Strong Constraints on Fuzzy Dark Matter from Ultrafaint Dwarf Galaxy Eridanus II, PRL (2019) 123e1103M
Koushiappas & Loeb, Dynamics of Dwarf Galaxies Disfavor Stellar-Mass Black Holes as Dark Matter, PRL (2017) 119d1102K
2/28 Yijia Li Miyatake et al., Weak-lensing Mass Calibration of ACTPol Sunyaev-Zel'dovich Clusters with the Hyper Suprime-Cam Survey, ApJ (2019) 875, 63
3/6 Fan Zou Leclercq et al., The MUSE Hubble Ultra Deep Field Survey. VIII. Extended Lyman-α haloes around high-z star-forming galaxies, A&A (2017) 608, 8
3/20 James Gurian Finkelstein et al., Conditions for Reionizing the Universe with a Low Galaxy Ionizing Photon Escape Fraction, ApJ (2019) 879, 36
3/27 Andrew Pellegrino, Gautam Nagaraj Planck Collaboration, Planck 2018 results. I. Overview and the cosmological legacy of Planck, arXiv:1807.06205
4/10 Joseph Tomlinson Villaescusa-Navarro et al., The Quijote simulations, arXiv:1909.05273
He et al., Learning to Predict the Cosmological Structure Formation PNAS (2019) 116 (28) 13825-13832
4/17 Zhenyuan Wang Bose et al., Revealing the galaxy-halo connection in IllustrisTNG, MNRAS (2019) 490, 5693
5/1 Elijah Mathews Verde et al., Tensions between the Early and the Late Universe, arXiv:1907.10625

Lecture notes

Note that these notes are provided with no guarantees. Nobody (including me) has proofread the notes. Use at your own risk!

Links to Online materials

For some links below, you may need Penn State ID (or open the link on campus)

NASA/IPAC Extragalactic Database is a great online resource for extragalactic astronomy!

The top panel image is generated from MY GALAXIES website, where you can galaxify the text messages.

Distance measures in cosmology by David Hogg (astro-ph/9905116)
Ned Wright's cosmology calculator

A whole lot of nerby galaxies by David Hogg

Homework assignments

Solving problem sets is one of the most efficient ways of learning the subject. You are encouraged to collaborate with fellow students and/or to consult senior students, local postdocs and me. But, please write the solution by yourself.

No homework will be accepted after the solution is posted on the course webpage.

Eberly College of Science statements

1) The Eberly College of Science Code of Mutual Respect and Cooperation" www.science.psu.edu/climate/code-of-mutual-respect-and-cooperation-1 embodies the values that we hope our faculty, staff, and students possess and will endorse to make The Eberly College of Science a place where every individual feels respected and valued, as well as challenged and rewarded.

2) The Eberly College of Science is committed to the academic success of students enrolled in the College's courses and undergraduate programs. When in need of help, students can utilize various College and University wide resources for learning assistance. http://www.science.psu.edu/advising/success//

Academic Integrity Policy:

All Penn State policies regarding ethics and honorable behavior apply to this course (see links below for policy statements). Academic integrity is the pursuit of scholarly activity free from fraud and deception and is an educational objective of this institution. All University policies regarding academic integrity apply to this course. Academic dishonesty includes, but is not limited to, cheating, plagiarizing, fabricating of information or citations, facilitating acts of academic dishonesty by others, having unauthorized possession of examinations, submitting work of another person or work previously used without informing the instructor, or tampering with the academic work of other students. For any material or ideas obtained from other sources, such as the text or things you see on the web, in the library, etc., a source reference must be given. Direct quotes from any source must be identified as such. All exam answers must be your own, and you must not provide any assistance to other students during exams. Any instances of academic dishonesty WILL be pursued under the University and Eberly College of Science regulations concerning academic integrity.

Note to Students with Disabilities:

Penn State welcomes students with disabilities into the University's educational programs. If you have a disability-related need for reasonable academic adjustments in this course, contact the Office for Disability Services (ODS) at 814-863-1807 (V/TTY). For further information regarding ODS, please visit the Office for Disability Services Web site at http://equity.psu.edu/ods/ . In order to receive consideration for course accommodations, you must contact ODS and provide documentation (see the documentation guidelines at https://equity.psu.edu/ods/guidelines). If the documentation supports the need for academic adjustments, ODS will provide a letter identifying appropriate academic adjustments. Please share this letter and discuss the adjustments with your instructor as early in the course as possible. You must contact ODS and request academic adjustment letters at the beginning of each semester.