Judah Van Zandt

Biography

I am a postdoctoral researcher interested in the formation, evolution, and demographics of extrasolar planets. I received my Ph.D. from UCLA in 2025, with my dissertation focused on the relationship between close-in small planets and long-period gas giants.

I study planets at the population level through large ground- and space-based surveys. I am particularly interested in giant planets, which heavily influence their surroundings.

Selected Publications

Van Zandt, Judah, Bowler, Brendan P., et al. “The γ Cephei System: Updated Orbits, Dynamical Architecture, and Limits on Additional Companions.” Accepted to The Astronomical Journal (2026). https://arxiv.org/abs/2608.30030

Van Zandt, Judah, Bowler, Brendan P., et al. “Gaia Exoplanet Orbits, Demographics, and Evolution Survey (GEODES). I. Characteristics of Three Long-Period Companions Accelerating Their Host Stars.” The Astrophysical Journal 1006, 222 (2026). https://doi.org/10.3847/1538-4357/ae74cd

Van Zandt, Judah, Gilbert, Gregory J., et al. “A Smooth Transition from Giant Planets to Brown Dwarfs from the Radial Occurrence Distribution.” The Astronomical Journal 171, 267 (2026). https://doi.org/10.3847/1538-3881/ae5102

Gilbert, Gregory J., Van Zandt, Judah, et al. “Orbital Eccentricities Suggest a Gradual Transition from Giant Planets to Brown Dwarfs.” The Astronomical Journal 171, 67 (2026). https://doi.org/10.3847/1538-3881/ae1fd7

Van Zandt, Judah, Petigura, Erik A., et al. “The TESS–Keck Survey. XXIV. Outer Giants May Be More Prevalent in the Presence of Inner Small Planets.” The Astronomical Journal 169, 235 (2025). https://doi.org/10.3847/1538-3881/adbbed

Van Zandt, Judah. “The Prevalence of Distant Giant Planets in the Presence of Close-In Small Planets.” Ph.D. dissertation, University of California, Los Angeles (2025). https://escholarship.org/uc/item/2hh9c090

Van Zandt, Judah, and Petigura, Erik A. “No Evidence for a Metallicity-dependent Enhancement of Distant Giant Companions to Close-in Small Planets in the California Legacy Survey.” The Astronomical Journal 168, 268 (2024). https://doi.org/10.3847/1538-3881/ad8c3b

Lubin, Jack, Petigura, Erik A., Van Zandt, Judah, et al. “The HD 191939 Exoplanet System Is Well Aligned and Flat.” The Astronomical Journal 168, 196 (2024). https://doi.org/10.3847/1538-3881/ad79ed

Van Zandt, Judah, and Petigura, Erik A. “ethraid: A Simple Method for Characterizing Long-Period Companions Using Doppler, Astrometric, and Imaging Constraints.” The Astronomical Journal 167, 250 (2024). https://doi.org/10.3847/1538-3881/ad390b

Van Zandt, Judah, Petigura, Erik A., et al. “TESS-Keck Survey. XIV. Two Giant Exoplanets from the Distant Giants Survey.” The Astronomical Journal 165, 60 (2023). https://doi.org/10.3847/1538-3881/aca6ef