BS Astrophysics at California Institute of Technology

Programme overview

Teaches the basic facts and concepts of modern astronomy and astrophysics, stimulates interest in research and provides a basis for graduate work in the field.

Faculty: Division of Physics, Mathematics and Astronomy | Department: Astronomy | Duration: 4 years (12 terms of enrollment; 486 units of passing grades required) | Study mode: full-time | Intake: Fall | Location: Pasadena, CA, United States

What you will study

Required core Ay 20, Ay 21, Ay 101, Ay 102, Ay 30 or Ay 141, Ay 31, Ma 2, Ma 3, sophomore physics (Ph 2 abc or Ph 12 abc), Ph 125 ab and Ph 106 ab; three laboratory/experimental courses, 63 additional units of Ay or Ph courses and 27 units of science or engineering electives outside the division.

Official programme page

Application information

Entry requirements

University-wide first-year admission (not major-specific; students enter an option after the common first year). Expected preparation: four years of math including one year of calculus, one year of physics, one year of chemistry, one year of biology recommended, four years of English, two years of history and/or social sciences. SAT or ACT required (individual subscores considered); two letters of recommendation (one STEM teacher, one humanities or social science teacher) plus a Secondary School Report and essays; English proficiency (TOEFL iBT, IELTS or Duolingo) for applicants whose first language is not English and who were not taught in English. Applications via Common App or QuestBridge; Restrictive Early Action deadline November 1, Regular Decision January 4, 2027. Caltech does not admit applicants who already hold a bachelor's degree from another institution (such applicants apply as transfers). Option continuation: Students whose grade-point average in the option subjects falls below 1.9 at the end of an academic year may be refused permission to continue in the option.

USD 68,574 a year (2026-27). Tuition only for full-time undergraduates in 2026-27 (excludes student fees, housing and food). Same rate for all undergraduates; tuition is billed for 12 terms. Source

First-year entry is in the fall term. Caltech does not admit transfer students for the winter or spring terms.

First-year applicants apply through the Common App or the QuestBridge Application. Restrictive Early Action applications are due November 1, 2026 (decision by mid-December; reply by May 1, 2027); Regular Decision applications are due January 4, 2027 (decision by mid-March). The application fee is $85. SAT or ACT scores are required (scores due before November 30, 2026 for Restrictive Early Action and before December 31, 2026 for Regular Decision).

Transfer applications are due February 1, 2027, with transfer exams due February 15, 2027, notification in mid-April and a reply deadline of June 1, 2027. The transfer application fee is $85, paid through the Beaver Breakroom application portal.

Apply through the official page: https://www.admissions.caltech.edu/

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