I’m broadly interested in how we can extract maximal information from complex astrophysical data
across vastly different scales. My research trajectory spans multiple subfields. I began my PhD in
radio instrumentation at McGill University before transitioning to high-redshift theory at the
University of Melbourne. This transition deepened my understanding of astrophysics and cosmology,
allowing me to follow the story from the tiniest photon signal (or a voltage fluctuation) to the
reconstructed mass of a galaxy in the early Universe. After spending graduate school in
Canada and Australia, I will move back to the US to start as a McWilliams Postdoctoral Fellow at
Carnegie Mellon University in October, 2026.
How do my research interests fit together?
Along the way, my academic journey has spanned three countries and is complemented by
nearly a year of data science experience. I also worked as a data science intern at NASA Ames in
2019 and later as a physicist at Facebook (Meta) in 2021. Beyond astrophysics, I find balance
through coffee, solo travel, and vinyasa yoga. Follow my academic journey on Twitter at @sabrinastronomy and Linkedin.
I am a second-generation Filipina-American from Concord, California, with a multi-ethnic heritage
that blends Filipino roots from Puerto Princesa, Palawan, with Hispanic and white settler ancestry.
As a dedicated advocate for women of color in science, I actively mentor emerging scholars and
strive to lead by example through both my research and community engagement.
Brief Academic Timeline
PhD Candidate at University of Melbourne/ASTRO 3D
(2022-present)
Physics MSc at McGill University (2022)
Astrophysics BA at UC Berkeley (2018)
Hiking in New Mexico with my friend, Dillon Dong (also fellow astronomer)!Me, my mom, and my grandma!
Research
The publications I've been a part of can be found in this ADS library or
on Orcid.
I am passionate about research between infrared and radio wavelengths and bridging the divide
between theory and instrumentation. Although my
research experiences have been diverse, I have unified my work through both high performance
computing and data science applications.
High-z Theory
I work broadly on simulating the high-z universe (z ≥ 6) to compare to current and future
observations in the context of supermassive black hole growth.
Simulations meet space telescopes
The James Webb Space Telescope (JWST) has opened an unprecedented window into the early Universe.
It's revealed both the host galaxies of luminous quasars and the compact, red enigmas (AGN?Dense galaxies?) known as
Little Red Dots (LRDs). My work compares JWST detections of high-redshift quasar host galaxies and
LRDs to their analogs in hydrodynamic simulations. Using realistic mock JWST images and spectra, I
test how observational effects shape what we can (and can’t) measure. My current project builds a
simulation-based inference pipeline to quantify how these effects bias key galaxy properties, such
as the inferred stellar mass of quasar hosts — helping us uncover what JWST is truly revealing about
the first galaxies and black holes. See Berger+2024
and Berger+2025.
How biased are JWST stellar mass observations? We find that JWST PSF removal may
sometimes overestimate stellar masses leading to an even larger deviation from the low-z
relation.
Reionization
I apply Bayesian statistics and deep learning to future measurements of the universe during
reionization
to reconstruct the matter density field. The first paper on this work represents the first proof of
concept for field level inference using only Bayesian methods of 21-cm fields at high-z. Through the
use of maximum a posteriori (MAP) estimates and Hamiltonian Monte Carlo (HMC), we
successfully reconstruct the matter density field during reionization using a brightness temperature
measurement. This requires
the use of highly optimized auto-differentiation methods on GPUs (I use JAX ).
Output reconstructed map of the 21 cm brightness temperature from an HMC with 10k+
parameters (yes, that means 10k+ posteriors)! Recovery on small scales are still difficult — let
me know how you recover small scales :)
Radio Instrumentation
During my master's degree at McGill University, I worked on calibrating
radio telescopes using both traditional and novel techniques with Jonathan Sievers. I made the first proof of
concept measurement using GPS satellites to calibrate radio dish telescopes. I measured
consistent and repeatable satellite slices through the pathfinder of Canada's next leading radio
telescope: Canadian Hydrogen Observatory and
Radio transient Detector (CHORD). I also explored the use of GNSS in VLBI phase calibration
in comparison to classic pulsar calibrators.
Check out the paper and GitHub if you are interested. Or if
you're really interested, you can check out my Master's thesis !
Averaged beam measurements for several GPS satellites above the CHORD pathfinder. We
found a minimum difference of 0.56 db-Hz in the main beam for multiple passes.The initial testing data for this project were collected in some pretty cool places—like
the rooftops of McGill University and the UT Austin Physics Department!
Industry Experience
Did you know that a Facebook employee claims to have invented the job title
data scientist
?
Facebook
NASA
Teaching
I started my teaching journey as a community college student where I tutored introductory astronomy
courses. Working with students from diverse backgrounds, including English language learners and those
with additional needs, has taught me the importance of adaptability and empathy in education. Having had
limited opportunities to experience active learning in my own education (see this article if you're
interested in learning more about what active learning is), I strive to incorporate active
learning into all my teaching experiences.
University Teaching
As a graduate TA and tutor, I have been able to put my teaching skills into practice and further my
confidence as a teacher.
I have taught tutorials, held office hours, made solution sets, and graded while a TA.
University of Melbourne (During PhD)
The Art of Scientific Computing (Summer/Winter 2023)
Special Relativity (Winter 2023)
McGill University (During MSc)
Signal Processing (Spring 2021/2022)
Introduction to Astrophysics (Mixed Honors Undergraduate and Graduate Course) (Fall 2021)
Computational Physics with Applications (PHYS 512) (Mixed Honors Undergraduate and Graduate
Course) (Fall 2019)
Delivered 25 hours of lectures on Python concepts each month.
Provide 1 on 1 tutoring, mentorship, and homework and final project feedback.
Helped 150+ women and non-binary students of all ages learn Python for the first time.
Here's some student feedback I received while at Hackbright that embodies my teaching style: "I
appreciate your empathy and welcoming tone when you present. I honestly don't feel so dumb when
I provide incorrect answers to reviews or random questions because that's the environment you've
created. It's a safe space and I wish you could teach the August full time cohort!!"
Coding Workshops
McGill Physics Hackathon (Introduction to Machine Learning), 20+ students (2021)
McDonald Particle Physics Summer School (Introduction to Unix/Linux), 100+ students (2021)
Private Tutoring
Over the years, I also spent 150+ hours as both a group and private physics and programming tutor to
elementary through university students. This involved crafting sample problems and providing
mini-lectures on the subject matter. (January 2016 - present)
Outreach
New!
First off, check out this podcast episode I did with one of my favorite astronomers,
Dr. Charles Liu, very recently! I discuss my path into science and research so far.
I outline much of my outreach experience in depth below. Or checkout my CV
for a full list.
astro[sound]bites
Since 2022, I’ve been a co-host for the astro[sound]bites
podcast , the podcast spin-off of astrobites .
astro[sound]bites provides an accessible avenue for anyone interested in astronomy to learn about
exciting research at the undergraduate level.
Every other week, we synthesize two astrobites from across the spectrum of astrophysics subfields and
unify them into a fun and cohesive theme. We also host episodes on topics related to equity and
inclusion within astronomy. As of January, 2025, our episodes have amassed more than 27,000 downloads.
Below are three of the episodes I'm most proud of. In Episode 68, I give an overview of my atypical path
into astronomy.
I began participating in astronomy related public engagement as soon as I chose my major.
My first experience was as a volunteer at the local Chabot Space and
Science Center
near me in 2013. Since then, my passion for participating in public engagement went into full force. I
became an
American Astronomical Society
(AAS) Astronomy Ambassador
while at UC Berkeley, which included a two-day workshop on best practices in science public engagement.
Outreach/Hackathon Coordinator at McGill
I served as a McGill
Physics Matters Outreach Coordinator throughout 2020. While in this role, I co-led the organization of
the
McGill
Physics Hackathon in November,
2020 which included organizing eight coding workshops on Python to Machine Learning attended by
more than 200 people. I also
helped organize and facilitate a variety of programs and public astronomy talks supporting outreach in
the Montreal community and beyond.
This included initiating an ongoing international collaboration with the McGill Space Institute and
Dyer Observatory at Vanderbilt University
during the COVID-19 pandemic.
Outreach in Underserved Communities
As I participated more in outreach, I found that my main interest lies in reaching those who have not
had as much access to science engagement programs. I strive to target my public engagement almost
entirely to underserved communities. Through the Astronomy of the Pacific's Project
ASTRO Teacher Program (September 2016 - June 2017), I developed curriculum and instructed a
fifth-grade class in astronomy at Rosa Parks Elementary School in Richmond, California. Since then, I
also participated in a month long active learning and feedback workshop through the AAS and Astronomical
Society of the Pacific that culminated in a presentation to Fischer Middle School students in San Jose,
California in 2021.
Public Talks
I’ve also given invited talks on my research and my path through science at
