Researchers released the first major findings from the MEGATRON project in the Open Journal of Astrophysics, linking James Webb Space Telescope observations of infant galaxies with chemical fossils in ancient Milky Way stars through a multi-year cosmological simulation.
Elements that make our world and life possible—such as carbon, oxygen, and iron—were forged inside stars that lived and died billions of years ago. Tracing those origins required bridging two distinct astronomical perspectives that previously remained unconnected.
Project Connects Early Galaxies to Ancient Stars
Led by researchers at the University of Bath in the U.K., alongside collaborators at the University of Chicago and the Institut d’Astrophysique de Paris, the MEGATRON project began in 2023 and is scheduled to run until 2030. The collaboration utilized advanced cosmological radiation-hydrodynamics simulations to explore how the universe’s first stars and galaxies lit up the dark cosmos and enriched it with heavy elements.
Accurately capturing the interplay between starlight, gas, and newly forged elements is essential for interpreting emerging data. According to the reporting, the project combines cosmological simulations with sophisticated models of radiation, chemistry, and galaxy formation.
“The elements that make our world and life possible – carbon, oxygen, iron and many others – were forged by stars. To understand where those elements came from, we need to understand how the first stars formed and enriched their surroundings, MEGATRON allows us to test these ideas directly by comparing detailed simulations with observations from JWST and the chemical fingerprints preserved in ancient stars.”
Dr Martin Rey, Department of Physics at the University of Bath
Dr Martin Rey, a lead contributor to the MEGATRON collaboration from the Department of Physics at the University of Bath, noted that the James Webb Space Telescope gives a direct glimpse of the infant cosmos, while stellar archaeology allows astronomers to study the relics of those earliest times in our own galactic neighborhood, with MEGATRON providing a physical bridge between the two.
Supercomputers Model Milky Way Ancestors
The project was awarded 40 million processor hours on U.K. national supercomputers, an equivalent workload to running five million laptops in parallel for a full year.
MEGATRON focused on a zoomed cosmological region destined to develop into a Milky Way-mass system.
The simulations incorporate radiative transfer and non-equilibrium chemistry involving more than 80 primordial species, molecules, and metal ions.
Harley Katz, assistant professor of astronomy and astrophysics at the University of Chicago and lead scientist on the simulation work, noted the unprecedented scale of the modeling.
“What does the Milky Way look like at what we call cosmic dawn? For the first time, we can directly predict what the early Milky Way would have looked like to telescopes like Hubble or the James Webb Space Telescope.”
Harley Katz, Assistant Professor of Astronomy and Astrophysics at the University of Chicago
Simulations Address the Iron Plateau Mystery
Smaller and fainter galaxies contain less iron than massive ones. One of the most notable results from the initial batch of papers addresses this enduring astronomical enigma known as the iron plateau.
According to the calculations, most of these tiny galaxies received their iron from a single explosion of an extremely massive first-generation star.
Collaboration Targets Completion by 2030
With the publication of the first four studies in the Open Journal of Astrophysics, the research team is already working on the next generation of models. As the James Webb Space Telescope continues gathering data on the earliest galaxies and large-scale stellar surveys map ancient stars in our cosmic backyard, researchers plan to refine their simulations further.
The collaboration aims to strengthen links between theoretical frameworks and emerging observations as the project continues toward its scheduled completion in 2030.