Research Interest

"The reward of the young scientist is the emotional thrill of being the first person in the history of the world to see something or to understand something." - Cecilia Payne-Gaposchkin


Formation of the Milky Way


Chemical tagging


Near field cosmology


Machine learning


Stellar spectra


Stellar populations

I study the Milky Way

"We are part of this universe; we are in this universe, but perhaps more important than both of those facts, is that the universe is in us." - Neil deGrasse Tyson

The big picture

Understanding all physical processes responsible for the formation and evolution of galaxies is a fundamental, but unsolved problem in astrophysics.

Why study the Milky Way

Our own galaxy, the Milky Way, offers a unique chance to study the formation and evolution of the structural components of a galactic system (disk, bulge, and halo) because it is the only galaxy for which we can study individual stars in great detail.

What to study about the Milky Way

We still do not have a detailed picture of when, where, and how stars in each component of the Milky Way formed, nor of the key processes responsible for its full dynamical and chemical evolution.

My research

My research shines new light on chemodynamical modeling and spectral fitting with cutting-edge machine learning techniques to unravel the history of the Milky Way through “Galactic Archaeology.” In particular, I have developed tools to implement a powerful idea known as “chemical tagging.”

What is chemical tagging

Like twins separated at birth, stars in the Milky Way formed in clusters but were soon torn apart. The goal of chemical tagging and my research is to recognize stars as birth-siblings by their unique “chemical fingerprint,” even if they are on widely dispersed orbits and spatially mixed.

Public Outreach

"All men have stars, but they are not the same things for different people. For some, who are travelers, the stars are guides. For others they are no more than little lights in the sky. For others, who are scholars, they are problems." - The Little Prince

TED Video: How do we study the stars

TED Video: How to measure distances

Interactive Modules: Interstellar Absorption and the Lyman Alpha Forest


"The struggle itself towards the heights is enough to fill a man's heart. One must imagine Sisyphus happy." - Albert Camus

Download Resume

Professional Appointment


Hubble Postdoctoral Fellow

Funded by NASA for a fully independent postdoctoral research.


Member of the Institute for Advanced Study in Princeton


Joint Carnegie-Princeton-IAS Fellow

Joint postdoctoral fellowship from Princeton University, the Institute for Advanced Study in Princeton (where Albert Einstein worked!) and the Carnegie Observatories (where Erwin Hubble worked!).


Interim Postdoctoral Research Associate, Australian National University



Harvard University -- PhD Astrophysics

Advisor: Prof. Charlie Conroy


Ecole Polytechnique, France -- MSE, BSE Engineer's Degree

Diplome D'Ingenieur de l'Ecole Polytechnique
Equivalent to Master's and Bachelor's Degrees in Engineering
Concurrent double degrees from Singapore and France


National University of Singapore -- MSc, BSc Mathematical Physics

Best Physics major in Singapore
Minor in Mathematics
Concurrent double degrees from Singapore and France


Hubble Fellowship - 2018-21

Prized postdoctoral fellowship from NASA

Carnegie-Princeton Fellowship - 2017-23

A joint prized postdoctoral fellowship from the Carnegie Observatories and Princeton University

Institute for Advanced Study School of Natural Sciences Fellowship - 2017-21

Awarded full funding for an independent research at the Institute for Advanced Study, Princeton

Alexander von Humboldt Fellowship (declined) - 2017

Awarded full funding for an independent research in Germany

Dr. Pliny A. and Margaret H. Price Prize - 2016

Two finishing Ph.D.s awarded internationally

Selected to attend the Lindau Meeting of Nobel Laureates, Lindau, Germany

Prestigious meeting for young scientists below the age of 35

NASA Earth and Space Science Fellowship - 2015-16

Funded by NASA for a Ph.D. study

Malaysian Perdana Scholar Award - 2014

National merit award

Singapore National Academy of Science Award - 2012

Best Physics major in Singapore

Institute of Physics Singapore Medal - 2011

Best Physics undergraduate in Singapore

French Government Eiffel Scholarship - 2008-10

Full scholarship for a study in France

Jurong Book Prize, National University of Singapore - 2008

Best freshman/sophomore Physics major

Australian Mathematics Competition Gold Medal - 2005

Top 0.01% among entries from 8 countries

Research Milestones




First/second or student authored publications






Talks/ presentations


Invited talks


Metallicity fluctuation statistics in the interstellar medium and young stars. I. Variance and correlation
2018, MNRAS, in press.

Photospheric diagnostics of core helium burning in giant stars
2018, ApJ, 853, 20

Measuring 14 elemental abundances with R=1,800 Lamost spectra
2017, ApJL 849, L9

Prospect for measuring abundances of >20 elements with low-resolution stellar spectra
2017, ApJ, 843, 32

Constructing polynomial spectral models for stars
2016, ApJL, 826, L25

Accelerated fitting of stellar spectra
2016, ApJ, 826, 83

APOGEE chemical tagging constraint on the maximum star cluster mass in the α-enhanced Galactic disk
2016, ApJ, 816, 10

Prospects for chemically tagging stars in the Galaxy
2015, ApJ, 807, 104

Constraining the Galactic potential via action-based distribution functions for mono-abundance stellar populations
2013, MNRAS, 434, 652

High resolution elemental abundance analysis of the open cluster IC 4756
2012, MNRAS, 427, 882

Galaxy Zoo: Dust lane early-type galaxies are tracers of recent, gas-rich minor mergers
2012, MNRAS, 423, 59

Galaxy Zoo: Dust and molecular gas in early-type galaxies with prominent dust lanes
2012, MNRAS, 423, 49

Principal component analysis on chemical abundance spaces
2012, MNRAS, 421, 1231


"We cannot work without hoping that others will advance further than we have. In principle, this progress goes on ad infinitum. " - Max Weber

Intermediate Algebra

Princeton Prison Teaching Innitiative
Teaching assistant

Stellar astrophysics

Harvard University
Teaching assistant

Classical Mechanics

National University of Singapore
Teaching assistant


National University of Singapore
Teaching assistant


National University of Singapore

Linear Algebra

National University of Singapore

Abstract algebra

National University of Singapore

Contact Me

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