DrThemiya Nanayakkara

I am an observational astrophysicist in the Sydney Institute for Astronomy, studying how galaxies formed and evolved in the early Universe. Using major space- and ground-based observatories - principally the James Webb Space Telescope, the Very Large Telescope and Keck - I investigate how the first galaxies assembled, formed their stars, ceased forming them, and became enriched with heavy elements.

My work combines deep spectroscopy with stellar-population and photoionisation modelling. I have led spectroscopic studies revealing faint, old and massive galaxies in the early Universe and measuring how rapidly they formed and quenched, and I was part of the team that identified a massive galaxy which formed its stars at z = 11. I also work on chemical enrichment at cosmic dawn, on the role of low-luminosity galaxies in cosmic reionisation, and on the data-reduction and calibration pipelines that make large spectroscopic surveys reproducible.

Before joining Sydney I was Deputy Director and Senior Scientist at the JWST Australian Data Centre at Swinburne University of Technology, and a postdoctoral researcher at Leiden Observatory on the core science team for VLT/MUSE.