Scientists have developed a massive computer simulation that recreates the early evolution of the universe, offering new insights into how the first stars, galaxies and black holes emerged after the Big Bang.

The simulation, named Lumina, was created by researchers at the Center for Astrophysics | Harvard & Smithsonian in collaboration with scientists from other institutions. The findings were published in the journal Monthly Notices of the Royal Astronomical Society and reported in science coverage on October 2026.

The project aims to help astronomers understand how the universe transformed from an early cosmic environment into the complex structure observed today.

How Lumina Recreates the Early Universe

Lumina models the interactions between ordinary matter, dark matter and radiation during approximately the first two billion years of cosmic history. By simulating these processes, researchers can investigate how early stars and galaxies formed and how their radiation changed the gas surrounding them.

One of the simulation’s major advances is its ability to model hydrogen and helium reionization together. During these processes, energetic radiation strips electrons from atoms, changing the properties of gas across enormous regions of space.

The research suggests that radiation from early stars and galaxies played a major role in hydrogen reionization, while energetic activity around supermassive black holes helped drive helium reionization.

Understanding these transformations is important because they influenced how light travelled through the young universe and how cosmic structures developed.

More Than 15,000 GPUs Used in the Project

Creating such a detailed model required extraordinary computing resources. The research team used more than 15,000 graphics processing units (GPUs) on the Frontier supercomputer at Oak Ridge National Laboratory in the United States.

The simulation covers a region roughly 1.5 billion light-years across on each side, making it substantially larger in volume than earlier comparable simulations. It also retains enough detail to investigate individual developing galaxies alongside much larger cosmic structures.

This combination of scale and detail gives researchers a way to study processes that are difficult to observe directly across such vast distances.

Connecting Simulations With Telescope Observations

Lumina is designed to help scientists compare theoretical predictions with real astronomical observations. Researchers can examine whether the simulated universe matches data collected by powerful observatories, including NASA’s James Webb Space Telescope.

These comparisons could help astronomers investigate the surprisingly complex galaxies found in the early universe and test existing explanations for how stars, galaxies and black holes developed.

If observations differ significantly from the simulation’s predictions, scientists may discover that current models need refinement or that important physical processes remain poorly understood.

A New Tool for Exploring Cosmic History

The Lumina project represents an important step in combining advanced computing with astronomy. Rather than relying only on observations of distant objects, scientists can use the simulation to explore how different physical processes may have interacted throughout early cosmic history.

The model does not provide a direct recording of the universe’s past. Instead, it offers a detailed scientific reconstruction based on established physical theories that can be tested against observations.

As more data becomes available from current and future telescopes, Lumina could help researchers develop a clearer picture of how the universe evolved during its earliest two billion years.