Junior Papers, Senior Theses, Senior Thesis Defenses

Junior Papers (Fall and Spring) and Senior Theses in Astrophysics represent original research work done by the student in collaboration with a faculty adviser. The work ranges from observational astronomy and data analysis to theoretical and computational astrophysics.  All topics in astronomy and astrophysics are covered, from planets, stars, and the interstellar medium to galaxies, quasars, large-scale structure of the universe, dark matter, dark energy, black holes, cosmology, the microwave background, and the early universe. These topics can be researched both theoretically and observationally.  The Astro Majors have a choice on what topic they wish to work for for each of their JPs and ST. Typically, each student will discuss possible choices with the Director of the Undergrad Program (Prof. Neta Bahcall) at the beginning of each term; Prof. Bahcall will advise the students of various possibilities and direct each student to discuss potential projects with a couple of faculty and researchers in the department. The student then selects the topic that most excites them. This is repeated for each of the JPs and for the Senior Thesis.

The department allows students to carry out a JP or a Senior Thesis in another department if relevant and appropriate for the future directions and goals of the student.  Some of our students have carried out a JP or a ST in departments or topics such as Physics, MAE, Philosophy, the WWS, Science Education, and more.  A student should discuss such possibilities with the Departmental Representative.

The Junior Paper and Senior Thesis do not have specific format requirements other than being similar to scientific papers published in professional journals; i.e., they should contain a concise Abstract, a comprehensive Introduction that reviews the general topic (more extensive than a typical publication), followed by presentation of the work itself -- the data or theory used, the analysis methods, the results, and the main Conclusions.  Figures, Plots, Tables are all expected in the paper. Many but not all of the Astro JPs and STs are eventually published as scientific papers in professional journals.

The department deadline for Fall JP is the University deadline (at the beginning of January).  The deadline for Senior Theses and Spring JPs  is typically the Friday before the university deadline (in early May) in order to reduce conflict with the special student celebrations that weekend.  For those students who need and request extra time, the deadline can be extended if needed up to the university deadline (which is on Mon-Tue immediately following that weekend).  Such requests should be made to the adviser (with a copy to Prof. Bahcall). No extension beyond this university deadline can be made without approval by the Dean (and none can be made for graduating Seniors).

All students are requested to provide drafts of their JPs and STs to their advisers before the deadline (a couple weeks prior to the deadline) in order to receive comments and improve their papers. Students will upload a PDF of their thesis, both for departmental review and for archiving at Mudd Library, via the centralized Senior Thesis Submission Site by the deadlines listed above.

Senior Thesis Defense

Seniors: together with your adviser, you need to select one additional reader for your thesis; the two faculty (adviser plus one reader) will comprise your thesis committee.

  • please give a copy of your thesis to the two members of your committee;

  • you will need to arrange a thesis defense date with your committee.  

The dates for the defense are usually within 1-2 weeks after the Thesis deadline. You need to reserve a room for that time with Polly Strauss (for about 1.5 hours). The THESIS DEFENSE is composed of three parts:

   A. THESIS: a 20 min presentation by the Senior of the thesis;
   B. THESIS DEFENSE: ~15 minutes questions by each of the two members of the committee on topics related to the thesis;
   C. GENERAL ASTROPHYSICS: ~15 minutes questions by each of the committee members on general topics in astrophysics (mostly based on topics covered in your classes). I suggest the students review the basic AST204 material (e.g. F. Shu's "The Physical Universe", Ryden & Peterson's "Foundation of Astro Physics", or other similar material. The idea is for the students to know basic Astrophysics. (The grade on this portion of the exam does not appear on the transcript.)

The department needs 2 bound copies of your final thesis:  one for the Lewis Library, and one for the department which should both be given to Polly Strauss.

JP and ST Grading Guidelines in Astrophysics

A+    Exceptional. Significantly exceeds the highest expectations for undergraduate work. The work should reflect a high degree of originality, independence, and understanding by the student, and contain important scientific results. The content and the presentation of the JP/ST should be at the level of a refereed journal article, and it is expected that after additional work the JP/ST will be submitted for publication.

A      Outstanding. Meets the highest standards for the assignment. Work that goes beyond simply "doing a good job". Should reflect originality and independence, excellent understanding of the topic, and high-level of presentation. At this grade level, an ST should contain important scientific results. A JP should either contain important results or demonstrate exceptional development in mastering the tools of original research in astrophysics, as applied to an important problem. In either case, it is generally expected that the student will eventually appear as co-author on a likely refereed publication.

A-    Excellent. Meets very high standards for the assignment. Between A above and B+ below.

B+    Very good. Meets high standards for the assignment. Student did what is expected at a very good level. At this level, the JP or ST will exhibit problems in either science content, understanding, presentation, or independence, and will look like it could have been improved with more work. An ST should contain substantial contributions toward the solution of an important research problem, and a JP should either contain such contributions or demonstrate significant development in mastering the tools of original research in astrophysics.

B     Good. Meets most of the standards for the assignment. The content, presentation, understanding, or independence of the student could stand some significant improvement.

B-    More than Adequate. Shows some reasonable command of the material. The content, presentation, understanding, or independence of the student is more than adequate but less than good. The work may contain some conceptual or other errors, and the work may reflect adequate but not good understanding, originality or independence.

C+   Acceptable; meets basic standards for the assignment.

C   Acceptable; meets some of the basic standards for the assignment.

C-  Acceptable; but falling short of meeting basic standards in several ways

D    Minimally acceptable; lowest passing grade

F     Fail. Very poor performance.

For students completing JP/ST in other departments the guidelines should be similar in spirit, but should take account of the different nature of the field.

Thesis Defense Grade

Each senior presents their thesis during the final oral Thesis Defense. The senior will typically present the Thesis in about 20 minutes. This presentation is followed by ~30 minutes of questions on the Thesis and Thesis-related topics: each of the two members of the Thesis committee has about 15 minutes each.

The grade on the Thesis defense will be decided by the committee based on the student presentation of the Thesis, the student answers to the questions on the Thesis, their general understanding of the Thesis topic and its execution, and their understanding of the broader Thesis-related topics.

A+ : outstanding knowledge, understanding, and presentation of the Thesis work, results, and the broader scientific topic.

A : excellent/very-good knowledge, understanding and presentation of the Thesis work, results, and broader scientific topic.

A- : very good (on above items); some misses in either the knowledge, understanding, or presentation

B+ : good; some of the knowledge, understanding, or presentation could have been better

B : some lack of knowledge or understanding of the project

B- or below: more substantial lack of knowledge or understanding of the Thesis work and related topics.

In addition, of course, each student will receive a grade on their Senior Thesis itself, following the ST guidelines listed above.

Astrophysics Comprehensive (Oral)

This is the third part of the final oral defense for seniors: 30 minutes of questions (15 minutes by each member of the committee) on general topics in astronomy and astrophysics. We generally recommend to the students to review F. Shu's introductory book in Astronomy, "The Physical Universe," as well as their class notes from their upper-level Astro courses. 

The grade on this part of the exam does not appear on the student transcript; it is only averaged together with other grades into an overall "Senior Departmental Exam."

For this grade, the grading guidelines are equivalent to those listed above for the Thesis Defense, but of course apply to the student's general knowledge of Astrophysics.

Examples of Astro JPs & Senior Theses


A Search for High Redshift Type II Quasars from the SDSS BOSS Survey (rmalexan.pdf)

JP, By Rachael M. Alexandroff


New Frontiers in Exoplanet Detection: High Contrast Imaging with Subaru (dressingThesis.pdf)

Senior Thesis, By Courtney Danielle Dressing


Where Are the Missing Baryons in Clusters? (bilhudathesis-2.pdf)

Senior Thesis, By Bilhuda Rasheed


Simulations of External Shocks in Gamma-Ray Bursts (wellonsthesis-1.pdf)

Senior Thesis, By Sarah Wellons