52 Hillhouse Avenue, 203.432.3000
M.S., M.Phil., Ph.D.

Sarbani Basu

Director of Graduate Studies
Jeffrey Kenney (203.432.3013,

Professors Charles Bailyn, Charles Baltay (Physics), Sarbani Basu, Paolo Coppi, Pierre Demarque (Emeritus), Debra Fischer, Marla Geha, Jeffrey Kenney, Richard Larson (Emeritus), Gregory Laughlin, Priyamvada Natarajan, C. Megan Urry (Physics), William van Altena (Emeritus), Pieter van Dokkum, Robert Zinn

Associate Professors Héctor Arce, Reina Maruyama (Physics), Daisuke Nagai (Physics), Nikhil Padmanabhan (Physics), Frank van den Bosch

Assistant Professor Jessi Cisewski (Statistics & Data Science), Laura Newburgh (Physics)

Fields of Study

Fields include observational and theoretical astronomy, solar and stellar astrophysics, exoplanets, the interstellar medium and star formation, astrometry, galactic astronomy, extragalactic astronomy, radio astronomy, high-energy astrophysics, and cosmology.

Special Admissions Requirements

Applicants are expected to have a strong undergraduate preparation in physics and mathematics. Although some formal training in astronomy is useful, it is by no means a prerequisite for admission. Applicants are required to take the General GRE as well as the subject test in Physics.

Special Requirements for the Ph.D. Degree

A typical program of study includes twelve courses taken during the first four terms, and must include the core courses listed below:

The Physics of Astrophysics (ASTR 500), Computational Methods in Astrophysics and Geophysics (ASTR 520), Observational Astronomy (ASTR 555), Interstellar Matter and Star Formation (ASTR 560), either Stellar Populations (ASTR 510) or Stellar Astrophysics (ASTR 550), and either Galaxies (ASTR 530) or The Evolving Universe (ASTR 565). ASTR 620 or PHYS 678 may be substituted for ASTR 520 with the permission of the director of graduate studies (DGS).

Students require the permission of the instructor and the DGS to skip a core class if they think that they have sufficient knowledge of the field. Students will be required to demonstrate their knowledge of the field before they are allowed to skip any core class.

Two of the twelve courses must be research credits, each earned by working in close collaboration with a faculty member. Of the two research credits, one must be earned doing a theoretical research project and one doing an experimental research project. The students need to present the results of the project as a written report and will be given an evaluation of their performance.

The choice of the four remaining courses depends on the candidate’s interest and background and must be decided in consultation with the DGS and/or the prospective thesis adviser. Advisers may require students to take particular classes and obtain a specified minimum grade in order for a student to work with them for their thesis. Students must take any additional course that their supervisors require even after their fourth term. In addition, all students, regardless of their term of study, have to attend Professional Seminar (ASTR 710 and ASTR 711) every term. Students must also take Responsible Conduct in Research for Physical Scientists (PHYS 590), which discusses ethics and responsible conduct in scientific research and fulfills the requirement stipulated by the National Science Foundation for all students and for all postdoctoral researchers funded by the NSF. Note that ASTR 710, ASTR 711, and PHYS 590 may not be used to fulfill the twelve-course requirement.

Students are encouraged to take graduate courses in physics or related subjects. On an irregular basis, special topic courses and seminars are offered, which provide the opportunity to study some fields in greater depth than is possible in standard courses. To achieve both breadth and depth in their education, students are encouraged to take a few courses beyond their second year of study.

There is no foreign language requirement. A written comprehensive examination, normally taken at the end of the fourth term of graduate work, tests the student’s familiarity with the entire field of astronomy and related branches of physics and mathematics. Particular attention will be paid to the student’s performance in the field in which the student plans to do research. An oral examination, held a few weeks after the written examination, is based on the student’s chosen field of research. Satisfactory performance in these examinations, an acceptable record in course and research work, and an approved dissertation prospectus are required for admission to candidacy for the Ph.D. degree. The dissertation should present the results of an original and thorough investigation, worthy of publication. Most importantly, it should reflect the candidate’s capacity for independent research. An oral dissertation defense is required.

Teaching experience is an integral part of graduate education in astronomy. All students are required to serve as teaching fellows for four terms. Both the level of teaching assignments and the scheduling of teaching are variable and largely determined by the needs of the department. Most students will teach in each of their first three terms and complete their fourth teaching assignment sometime after the qualifying exam.

Honors Requirement

Students must earn a grade of Honors in at least three classes by the end of the fourth term of full-time study and have a grade average of High Pass or better.

Master’s Degrees

M.Phil. Upon application, the department will recommend for the award of the M.Phil. degree any student who has completed all the requirements of the Ph.D. degree except the oral examination, which is based on the student’s chosen field of research, and the Ph.D. dissertation. A written master’s thesis containing original astronomical research is also required. Students are not admitted for this degree.

M.S. (en route to the Ph.D.) Upon application, the department will recommend for the award of the M.S. degree any student who has taken at least ten courses (not including ASTR 710 and ASTR 711), including at least one research project (ASTR 580). The student should have a grade average of High Pass in the courses and a grade of High Pass or above in the research project.

Program materials are available upon request to the Director of Graduate Studies, Department of Astronomy, Yale University, PO Box 208101, New Haven CT 06520-8101.


ASTR 500a, The Physics of AstrophysicsPriyamvada Natarajan

Primarily for incoming students in the Ph.D. program in Astronomy. The basic physics and related mathematics needed to take the advanced graduate courses. Topics in mechanics, thermodynamics and statistical mechanics, fluid mechanics, special relativity, and electrodynamics with applications to astrophysical systems are covered. Open to undergraduates with permission of the instructor.
TTh 4pm-5:15pm

ASTR 520a / G&G 538a, Computational Methods in Astrophysics and GeophysicsPaolo Coppi

The analytic and numerical/computational tools necessary for effective research in astronomy, geophysics, and related disciplines. Topics include numerical solutions to differential equations, spectral methods, and Monte Carlo simulations. Applications are made to common astrophysical and geophysical problems including fluids and N-body simulations.
MW 4pm-5:15pm

ASTR 545b / S&DS 570b, YData: ExoStatistics: Exploring Extrasolar Planets with Data ScienceJessica Cisewski

Extrasolar planets, or exoplanets, are planets orbiting stars outside our solar system. The past decade has led to a proliferation of exoplanet discoveries using various detection methods. Through the lens of data science, we investigate exoplanet datasets to learn how to find exoplanets, examine the population properties of observed exoplanets, estimate probabilities of another Earth-like exoplanet in our universe, and probe other questions about exoplanets. This course provides an introduction to exoplanet astronomy, an introduction to data science tools necessary for studying exoplanets, and opportunities to practice the data science skills presented in S&DS 523. This course can be taken concurrently with, or after successful completion of, S&DS 523.  ½ Course cr
T 3:30pm-5:20pm

ASTR 550a, Stellar AstrophysicsSarbani Basu

An introduction to the physics of stellar atmospheres and interiors. The basic equations of stellar structure, nuclear processes, stellar evolution, white dwarfs, and neutron stars.
TTh 9am-10:15am

ASTR 560b, Interstellar Matter and Star FormationHector Arce

The composition, extent, temperature, and density structure of the interstellar medium (ISM). Excitation and radiative processes; the properties of dust; the cold and hot ISM in the Milky Way and other galaxies. Dynamics and evolution of the ISM, including interactions between stars and interstellar matter. Physics and chemistry of molecular clouds and the process of star formation.
TTh 1pm-2:15pm

ASTR 565b, The Evolving UniversePieter Van Dokkum

Overview of cosmic history from the formation of the first star to the present day, focusing on direct observations of the high-redshift universe.
TTh 9am-10:15am

ASTR 580a or b, ResearchStaff

By arrangement with faculty.

ASTR 595b, Astrophysical FlowsGregory Laughlin

Fluid dynamics and hydrodynamics from an astrophysical perspective. The course covers the development of the Navier-Stokes equations from first principles, and discusses flows in which viscosity, gravity, radiation, and magnetic fields play dynamical roles (both separately and together). Specific applications to be covered include spherical collapse; the hydrodynamics of disks; and fluid waves, shocks, and fronts in a variety of contexts. We also discuss (and use) a variety of numerical schemes for solving fluid dynamical problems.
MW 9am-10:15am

ASTR 600b, CosmologyPriyamvada Natarajan

A comprehensive introduction to cosmology at the graduate level. The standard paradigm for the formation, growth, and evolution of structure in the universe is covered in detail. Topics include the inflationary origin of density fluctuations; the thermodynamics of the early universe; assembly of structure at late times and current status of observations. The basics of general relativity required to understand essential topics in cosmology are covered. Advanced undergraduates may register for the course with permission of the instructor.
TTh 4pm-5:15pm

ASTR 610a, The Theory of Galaxy FormationFranciscus van den Bosch

This astronomy course focuses on the physical processes associated with galaxy formation. Topics include Newtonian perturbation theory, the spherical collapse model, formation and structure of dark matter haloes (including Press-Schechter theory), the virial theorem, gravitational interactions, cooling processes, theory of star formation, feedback processes, and numerical simulations. The course also includes a detailed treatment of statistical tools used to describe the large-scale distribution of galaxies and introduces the student to the concepts of galaxy bias and halo occupation modeling. During the final lectures we discuss a number of outstanding issues in galaxy formation.
MW 9am-10:15am

ASTR 666a / AMTH 666a / G&G 666a, Classical Statistical ThermodynamicsJohn Wettlaufer

Classical thermodynamics is derived from statistical thermodynamics. Using the multi-particle nature of physical systems, we derive ergodicity, the central limit theorem, and the elemental description of the second law of thermodynamics. We then develop kinetics, transport theory, and reciprocity from the linear thermodynamics of irreversible processes. Topics of focus include Onsager reciprocal relations, the Fokker-Planck equation, stability in the sense of Lyapunov, and time invariance symmetry. We explore phenomena that are of direct relevance to astrophysical and geophysical settings. No quantum mechanics is necessary as a prerequisite.
TTh 10:30am-11:20am

ASTR 710a and ASTR 711b, Professional SeminarDebra Fischer

A weekly seminar covering science and professional issues in astronomy.
F 1:45pm-3:15pm