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Zoe Ko

View full CV in PDF form here.

Education

  • Johns Hopkins University
    Physics and Astronomy Ph.D. Student
    2024 – Present
  • University of California, Berkeley
    B.A. Astrophysics, B.A. Data Science
    2019 – 2023
    High Distinction in General Scholarship (magna cum laude equivalent)

Research Experience

  • Johns Hopkins University
    Research Assistant | Advisor: Néstor Espinoza | August 2024 – Present
    • Implemented a Gaussian Process-aided atmospheric retrieval framework to mitigate stellar contamination in transmission spectroscopy.
    • Applied retrieval framework to constrain the atmospheric properties of a gas giant orbiting an M dwarf to better understand giant planet formation around low mass stars.
    • Leading a first-author publication on current work.
  • California Institute of Technology LIGO Lab
    Research Intern | Advisor: Katerina Chatziioannou | June 2022 – January 2024
    • Developed and implemented a hierarchical Bayesian inference framework to analyze binary black hole spin distributions using LIGO gravitational wave data.
    • Generated mock binary black hole populations with different component spin parameters to quantify how much spin information is extractable from observed effective spins.
    • Presented findings at the American Physical Society April Meeting in April 2023 and co-authored a publication in Physical Review D.
  • University of California, Berkeley SETI Research Center
    Research Intern | Advisor: Howard Isaacson | June 2021 – January 2023
    • Developed and implemented a laser detection algorithm to search for potential technosignatures in optical stellar spectra.
    • Analyzed over 1,000 spectra of nearby stars to set detection limits.
    • Presented work at the Assembly of the Order of the Octopus (2021), AbSciCon 2022, and co-authored a publication in the Astronomical Journal.
  • Pennsylvania State University
    Research Assistant | Advisor: Ian Czekala | September 2019 – February 2023
    • Designed a data analysis pipeline to detect radial velocity variations by cross-correlating stellar spectra to calculate Doppler shifts.
    • Applied pipeline to search for radial velocity variations in 28 protoplanetary disk-hosting stars, identifying candidate spectroscopic binaries for follow-up study.
    • Authored a successful observing proposal for the Automated Planet Finder telescope in 2020 and led follow-up observations of a binary star candidate.

Awards and Fellowships

  • William H. Miller III Graduate Fellowship
    August 2024 – August 2025
    Awarded a 12-month fellowship from Johns Hopkins to support independent graduate research.
  • Fulbright Scholar
    September 2023 – July 2024
    Awarded a Fulbright English Teaching Assistant Scholarship.
    Designed and taught an English language curriculum for seventh and tenth grade students in a rural village in Northeast Thailand.
    Expanded mentorship and communication skills beyond STEM-focused environments.

Publications

  • Miller, S. J., Ko, Z., Callister, T., & Chatziioannou, K. 2024, "Gravitational waves carry information beyond effective spin parameters but it is hard to extract," Phys. Rev. D, 109, 104036
  • Zuckerman, A., Ko, Z., Isaacson, H., Croft, S., Price, D., Lebofsky, M., & Siemion, A. 2023, "The Breakthrough Listen Search for Intelligent Life: A Laser Search Pipeline for the Automated Planet Finder," AJ, 165, 114

Conference Talks and Posters

  • Z. Ko, N. Espinoza, A. Jordan. Mitigating Stellar Contamination in JWST Transit Data with Gaussian Processes, Exojamboree, Baltimore, MD, November 2025. (Oral Presentation)
  • Z. Ko, N. Espinoza, A. Jordan. A Gaussian Process Framework for Exoplanet Atmospheric Retrievals, Exoclimes V, Montreal, QC, Canada, July 2025. (Poster)
  • Z. Ko, N. Espinoza, A. Jordan. Gaussian Process Retrievals for TOI-3235b, Emerging Researchers in Exoplanet Science Symposium X, Princeton University, Princeton, NJ, June 2025. (Oral Presentation)
  • Z. Ko, S. J. Miller, K. Chatziioannou. Analyzing the Effective and Component Spin Distributions of Binary Black Hole Mergers, American Physical Society April Meeting, Minneapolis, MN, April 2023. (Oral Presentation)
  • Z. Ko, H. Isaacson, A. Zuckerman, S. Croft. Search for Laser Emission Lines with the Automated Planet Finder Telescope, American Astronomical Society Meeting, Seattle, WA, January 2023. (Poster)
  • Z. Ko, H. Isaacson, A. Zuckerman. Search for Laser Emission Lines with the Automated Planet Finder Telescope, AbSciCon, Atlanta, GA, May 2022. (Poster)
  • Z. Ko, H. Isaacson, A. Zuckerman, S. Croft. Search for Laser Emission Lines with the APF, Order of the Octopus, Virtual, August 2021. (Poster)

Skills

  • Programming: Advanced proficiency in Python (NumPy, SciPy, pandas, matplotlib, Astropy, etc.); also experienced with Java and R.
  • Statistical Modeling: Extensive experience with Bayesian inference frameworks (PyMC, emcee, dynesty) and Gaussian process modeling (tinygp, george, celerite).
  • Languages: Native fluency in English and Mandarin; strong proficiency in Spanish and Thai.

Teaching and Outreach

  • Physics and Astronomy Peer Mentor at Johns Hopkins
    August 2025 – Present
    Advise undergraduate students on research opportunities, graduate school applications, and career pathways in physics and astronomy through weekly mentoring sessions.
  • Peer Tutor at the Berkeley Student Learning Center
    August 2022 – May 2023
    Provided tutoring services for introductory astrophysics courses, supporting students with homework, lecture material, and exam preparation.