About

I am a fifth-year graduate student working with Ben Shappee, David Jones, and Chris Ashall on broad topics within time-domain astronomy. My primary research focus is type Ia supernovae and their subtypes, but I also work on other supernova types at high and low redshift, rarer transients such as tidal disruption events, and, lately, interstellar comets. My undergraduate research was on globular clusters.

Research

Ph.D. Topic

Topic: Rapid Observations of Infant Supernovae
Committee: Ben Shappee (Chair), Chris Ashall, David Jones, Gene Magnier, Jelena Maricic, Tony Piro

My research background includes type Ia supernovae, tidal disruption events, interstellar objects, and globular clusters. My publications in those areas are listed below. The link at the very bottom contains an ADS query for my name.

Publications

  • A Tale of Two Type Ia Supernovae: The Fast-declining Siblings SNe 2015bo and 1997cn (https://ui.adsabs.harvard.edu/abs/2022ApJ...928..103H/abstract)
  • A Careful Reassessment of Globular Cluster Multiple Population Radial Distributions with Sloan Digital Sky Survey and Johnson-Cousins Broadband Photometry (https://ui.adsabs.harvard.edu/abs/2021AJ....161..249H/abstract)
  • From Out of the Blue: Swift Links 2002es-like, 2003fg-like, and Early-Time Bump Type Ia Supernovae (https://ui.adsabs.harvard.edu/abs/2023arXiv230911563H/abstract)
  • Discovery and Follow-up of ASASSN-23bd (AT 2023clx): The Lowest Redshift and Least Luminous Tidal Disruption Event To Date (https://ui.adsabs.harvard.edu/abs/2024arXiv240105490H/abstract)
  • Seeing the Outer Edge of the Infant Type Ia Supernova 2024epr in the Optical and Near Infrared (https://ui.adsabs.harvard.edu/abs/2025OJAp....8E.120H/abstract)
  • Early and Extensive Ultraviolet through Near Infrared Observations of the Intermediate-luminosity Type Iax Supernovae 2024pxl (https://ui.adsabs.harvard.edu/abs/2025ApJ...988..209H/abstract)
  • Spatial Profiles of 3I/ATLAS CN and Ni Outgassing from Keck/KCWI Integral Field Spectroscopy (https://ui.adsabs.harvard.edu/abs/2025arXiv251011779H/abstract)
  • University of Hawaii 88-inch Telescope Observations of the Interstellar Comet 3I/ATLAS: Spectrophotometric Blue-Sensitive Spectral Time Series Spanning Two Months from Discovery (https://ui.adsabs.harvard.edu/abs/2025arXiv251209020H/abstract)
  • Postperihelion Integral Field Spectroscopy of the Interstellar Comet 3I/ATLAS (https://ui.adsabs.harvard.edu/abs/2026ApJ..1003..245H/abstract)
Publications

Awards

Honors

  • NSF Graduate Research Fellow
  • Goldwater Scholar
  • NSF INTERN
  • ARCS Scholar

Advisees

Students

Current
  • Leander "Leo" Derose (Hamilton College)
  • Oliver Kangwai (University of Hawaii, Hilo)
Previous
  • Ivan Abreu Paniagua (University of Rhode Island)
  • Grace Showerman (Michigan State University)
  • Valeria Aparicio (University of Hawaii, Manoa)

Willem Hoogendam

NSF Graduate Research Fellow
Extragalactic, Solar System Bodies, Stellar & Substellar, Surveys
B.S. Physics 2022, Calvin College
B.S. Mathematics 2022, Calvin College
M.S. Astronomy 2024, University of Hawaii
  • Supernovae
  • Tidal Disruption Events
  • Transients
  • Interstellar Objects and Comets
IfA Mānoa, B-227
willemh@hawaii.edu