Senior Lecturer, School of Physics · Sydney Institute for Astronomy
Hi, I’m Themiya Nanayakkara —
Astrophysicist working at the forefront of JWST-era galaxy formation. I study how the first generations of galaxies transformed the chemically simple early Universe into one enriched with the elements needed for planets and life — and I build the open tools and training that let researchers everywhere join the search.
I study how the first generations of galaxies transformed a chemically simple early Universe into one rich with the elements needed for planets and life — and I build the open tools and training that let researchers everywhere join the search.
I'm an astrophysicist working at the forefront of JWST-era galaxy formation. My research combines deep spectroscopic observations, multi-wavelength data and physical modelling to trace the formation histories, stellar populations and chemical evolution of galaxies across cosmic time.
I've contributed to some of the deepest surveys of the early Universe and led discoveries of the earliest known 'dead' galaxies — systems that formed and shut down within the Universe's first few hundred million years — placing strong constraints on how galaxies grow.
Alongside the science, I'm committed to mentoring, technical training and international capacity building, with a focus on expanding access to cutting-edge astronomical data and methods across the Global South.
Scroll from the first instant to the present day and watch the cosmos fill with the elements of planets, atmospheres and life — following the thread my research traces back to where that chemistry began.
My work spans deep spectroscopy, multi-wavelength data and physical modelling — from the first galaxies to the open methods that make frontier science reproducible.
I led JWST discoveries of the earliest known quiescent galaxies — systems that formed and switched off their star formation within the Universe's first few hundred million years — directly challenging established models of how galaxies grow.
Revealing unexpectedly rich heavy-element abundances and exotic signatures — extreme nitrogen, iron-rich ratios — in the earliest galaxies: evidence that the very first stars enriched the cosmos far faster than theory predicted.
Lead and collaborate with several JWST and large ground based suveys such as GLASS, UNCOVER, MINERVA, REBELS, PHOENIX, and Out-There.
I develop and teach reproducible, cloud-based analysis methods so researchers beyond the major observatory centres can take part in frontier space-science discovery.
From 2017 to 2025 — milestone papers charting the earliest galaxies and the chemistry of the infant Universe. Select a milestone to explore the result.
A peer-reviewed record tracing the earliest galaxies, the chemistry of the infant Universe, and the open tools that bring frontier data to everyone. Search and filter the highlights below.
Building long-term pathways for researchers to join frontier space science.
I supervise researchers across Australia and partner institutions, and build long-term mentoring pathways for students from under-resourced research environments into PhD programs worldwide.
I translate frontier discoveries about the cosmos for broad audiences through public lectures, school outreach, media and writing.
reads across four articles in outlets such as The Conversation.
From chairing the first global JWST symposium to steering Global-South training programs and Australia's astronomy strategy.
13 invited & keynote talks · colloquia at 15+ institutions worldwide.
From the JWST Australian Data Centre to observing runs on Maunakea and survey teams across three continents.
Collaborations, student & mentoring enquiries, media, or capacity-building programs — I'd love to hear from you.
School of Physics, The University of Sydney, NSW 2006, Australia