Research Interests

Within astrophysics I am broadly interested in stars, and I'm particularly interested in what the chemical abundances of stars can tell us about how planets form, all the way to how galaxies evolve. More broadly I am interested in physics, data analysis, statistical inference, machine learning, and information theory. Some of my research themes are listed below.

If you are a student interested in doing an astrophysics or statistics project then you should contact me because I give my most exciting research ideas to students, and those change as quickly as research does!

Revealing the Milky Way's history though chemical tagging

Stars form in groups, but then soon move away from each other. That means that where a star is now does not reflect where it was born, which makes it difficult to understand how our galaxy has evolved. Astronomers can measure the amount of different chemical elements (e.g., iron, calcium) in a star's photosphere, and these stay mostly the same throughout a star's life, giving each star a chemical fingerprint that reflects where and when it formed.

Using an approach called chemical tagging and a statistical principle called minimum message length, we're identifying stars that grew up together and have now moved apart, allowing us to 'rewind' the history of our galaxy.

Ancient stars and the high-redshift universe

Some stars are made of hydrogen, helium, and only tiny amounts of anything else. These stars are generally considered to be very old, because their chemistry is similar to what the universe was like soon after the Big Bang.

The positions, orbits, and detailed chemistry of these ancient stars are uniquely informative about the conditions of the early universe, and they connect our local Milky Way galaxy to the galaxies we see at high redshift.

The relationship between exoplanets and their host stars

Most stars host planets, but there is very little understanding on how the properties of a star can affect whether a planet forms, and what that planet will be like. Through precise chemical abundance measurements of stars that are known to host exoplanets, we're testing fundamental theories of planet formation, some of which critically depend on the amounts of different elements that are available when a planet forms.

(brief academic)

Curriculum Vitae



Australian Research Council DECRA Fellow
2019 - 2023

Monash University, Australia

Research Fellow in Astrophysics and Statistics
2017 - 2019

Monash University, Australia

Research Fellow in Astrophysics
2014 - 2017

Institute of Astronomy, University of Cambridge, UK


Doctor of Philosophy, Astronomy & Astrophysics
2010 - 2013

Australian National University

My doctoral thesis, A tale of tidal tails in the Milky Way, was supervised by Dr Stefan Keller, Professor Gary Da Costa, and Professor Brian Schmidt AC, FRS, FAA.

Bachelor of Aerospace Engineering (Honours)
2005 - 2008

Monash University

My honours project, A numerical investigation of a skip-and-feathered configuration for orbital re-entry, received a score of 98/100. Associate Professor Greg Sheard supervised this project.


  • A total of 90 peer-reviewed publications (submitted or accepted), including 13 as first author and 7 as second author
  • Cumulative citations: more than 4,300 (NASA, Google Scholar)
  • Hirsch index (h-index) of 29: 29 publications each with at least 29 citations
  • A h-index of 29 places me in the top 1% of Australian astronomers 6-10 years post-PhD, or in the top 25% of Australian astronomers 11-20 years post-PhD. As of February 2019 I am 5 years post-PhD.
  • Publication list includes articles in Nature (3), the Astrophysical Journal and its Supplement series, and the Monthly Notices of the Royal Astronomical Society, among others.

A complete list of my publications is available through the NASA Astrophysics Data Service.


Astronomy is a subject that can excite everyone. I enjoy giving regular public talks on astronomy to audiences with wide-ranging levels of background knowledge. I also give presentations to primary and high school students about: general astronomy; what it's like to be a scientist; and how research impacts our daily lives.

If you are:

  • a journalist seeking comments on a recent scientific discovery,
  • organising a public astronomy talk (or series), or
  • looking for an enthusiastic scientist to participate in a public outreach event,
then please contact me through the details below.



Dr Andrew R. Casey
School of Physics and Astronomy
Clayton Campus, Monash University
Wellington Road, Clayton, VIC 3800, Australia

andrew.casey {at}

+61 (0) 431 296 185