California Institute of Technology

PhD in Astrophysics

Pasadena, United States 4 years Taught in English Open to international students

Why students choose this program

  • Taught in English
  • Applications currently open

About PhD in Astrophysics

The application deadline for PhD in Astrophysics is Dec 21, 2026; tuition fees for PhD in Astrophysics are 60,816 USD per year.

The PhD in Astrophysics at California Institute of Technology is for students who have a Master's degree and want to study astrophysics in depth. This 4-year PhD program helps students develop advanced knowledge in physics. The program's main advantages include studying at a top university and being part of a strong research community.

The curriculum includes subjects like stellar astrophysics, planetary science, and cosmology. Students develop skills in data analysis, programming, and research methods. They also get hands-on experience with telescopes and other research equipment.

Graduates can work as Research Astronomers, Astrophysicists, or Science Writers. They can also find jobs as Professors or Researchers at universities and institutes. Top employers include NASA, the European Space Agency, and national observatories.

About California Institute of Technology

California Institute of Technology (Caltech) in Pasadena is internationally renowned for its focus on science and engineering and for a research environment that emphasizes discovery and innovation. Founded in 1891, Caltech combines small class sizes with world-class faculty and a culture that encourages independent inquiry. The institute’s achievements in fundamental research and technology transfer make it a top choice for students seeking an intensive STEM education and close mentorship from leading scholars.

Caltech offers a compact, high-impact academic setting where undergraduates and graduate students participate directly in cutting-edge projects across physics, biology, engineering and computation. Research opportunities are abundant and accessible, with students contributing to labs, observatories and centers that address global challenges. The collaborative, interdisciplinary approach cultivates both deep technical expertise and the ability to work across fields.

As a relatively small campus community, Caltech provides strong academic support, mentorship and networking in the greater Los Angeles research ecosystem. For international students drawn to rigorous STEM training, Caltech delivers concentrated resources, hands-on research experiences and pathways to meaningful scientific contribution in industry, academia and public service.

English Test Requirement

This program asks for IELTS 5.5-6.0. Here's what that's worth on the other tests universities accept, based on the official concordance tables:

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85–95

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TOEFL iBT
46–59
PTE Academic
42–49
CEFR level
B1/B2
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Equivalences are approximate — confirm the exact test and score the program accepts.

PhD in Astrophysics: Frequently Asked Questions

What are the fees for PhD in Astrophysics?
Tuition: USD 60,816 per year. Application fee: USD 105. Service fee: USD 100.
What are the entry requirements for PhD in Astrophysics?
Entry requirements include: Education: Master's Degree; Academic performance: Grade A (70%+, GPA 3+); English: IELTS 5.5-6.0; Minimum age: 18.
How long is the PhD in Astrophysics program?
The program duration is 4 year.
What is the application deadline?
The application deadline is 2026-12-21.
Is PhD in Astrophysics available online?
This is an on-campus program at California Institute of Technology in Pasadena.

Similar Programs You Can Apply To

Direct application via Global Admissions is not available for this program. Browse similar partner programs below or visit the university's site to apply directly.

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