My name is Fei Dai (戴飞). I'm currently a NASA Sagan fellow at Caltech. I will be starting a faculty position at the University of Hawaiʻi in February 2024. I am looking for students and postdocs. Please get in touch for possible collaborations.

Using both novel data analysis techniques and numerical simulations, I strive to understand the formation, evolution, and habitability of planetary systems. In particular, I focus on the most extreme planetary systems that look nothing like our Solar System including the "ultra-short-periods", the "super-puffs", planetary systems locked deep in resonance, and planetary systems dynamically tilted to polar orbits around their host stars. Previously I obtained my PhD in Physics from MIT under the supervision of Prof. Josh Winn.

Picture on the right was taken at Salar de Uyuni, Bolivia.

Research Highlights

  • Planetary Systems locked in a chain of mean-motion resonances likely produced by disk migration.

  • The Ultra-Short-Period: hellish worlds that orbit their host stars with periods as short as a few hours.

  • Puzzling low-density planets that should not exist.

  • Exotic Planets that orbit their host stars on polar or even retrograde orbits.

  • Starspots leave photometric signatures in planetary transit light curves which can unveil the orbital orientation and magnetic activity.

  • We extended the study of planet radius distribution (Fulton et al 2018) from Sun-like stars to M-dwarf planets. Results suggests that photoevaporation rather than core-powered mass loss is the main driver for the observed radius gap.

  • We studied the process of hydrodynamic atmospheric erosion with 3-D self-consistent simulations.

  • K2, the second phase of the NASA Kepler mission, enabled us to discover many exciting planetary systems along the ecliptic.

  • A pair of young stars that likely underwent a close encounter: a scenario that is supported by optical dimming, the tidal arms, and a strong Fe emission in X-ray.

  • Image credits: NASA/JPL-Caltech/T. Pyle, ESO/L. Calcada, Kley & Nelson, AAS Nova, Addison, Sanchis-Ojeda, Fulton, Haworth.


  • 111 All Publications
  • 13 First-Authored
  • 2548 Citations
  • 31 h-index
  • 68 i10-index

More up-to-date publication lists can be found here:

Community Service and Outreach

  • A free online workshop for undergraduate students aspiring to become an astronomer.

  • Check out some public talks I gave recently both in English and Mandarin Chinese.

  • I am a mentor for the Caltech WAVE Program: an undergraduate research program for underrepresented minority students.

Brief Bio

I was a graduate student at MIT Department of Physics from 2014 to 2019. I was also a visiting student at Princeton Univerity (2017-2019). Previously, I received B.A. in Natural Science and M.Sci in Physics from the University of Cambridge in 2014 with First Class Honours.