Researchers from the University of Nova Gorica are playing a central role in one of the most ambitious astronomical endeavors in history, the Legacy Survey of Space and Time (LSST) at the Vera C. Rubin Observatory in Chile. As the only Slovenian university with direct access to the project’s data, UNG’s Centre for Astrophysics and Cosmology has been embedded in the international collaboration since 2016, working alongside scientists from 26 countries to build an unprecedented decade long cinematic record of the cosmos. The project, which officially began its full survey operations in 2025, will capture billions of stars and galaxies and trillions of celestial changes, fundamentally altering how humanity observes the universe.
The Vera C. Rubin Observatory, perched on the Cerro Pachón mountain peak under the exceptionally clear skies of northern Chile, houses the Simonyi Survey Telescope and the largest digital camera ever constructed, a 3,200 megapixel instrument capable of producing images so vast that displaying one at full resolution would require 400 4K television screens. Each snapshot covers a field of view equivalent to 40 full moons, and the telescope will take a detailed image every 40 seconds, revisiting every corner of the southern sky approximately 800 times over the next decade. This relentless scanning will generate roughly 10 terabytes of data each night, accumulating to a dataset of about 30 petabytes by the survey’s completion. First light images released in June 2025 already demonstrated the observatory’s extraordinary capabilities, revealing over 10 million galaxies in the Virgo Cluster alone and detecting more than 2,000 previously unknown asteroids in just seven nights of preliminary observations.
At the heart of the Slovenian contribution is the search for tidal disruption events, cataclysmic occurrences where a star ventures too close to a supermassive black hole and is torn apart by gravitational forces, generating luminous flares that can outshine entire galaxies. Led by Professor Andreja Gomboc, the UNG team is specifically hunting these rare phenomena within the torrent of LSST data, using advanced machine learning methods to distinguish them from the thousands of other transients the telescope will detect nightly. Fellow researcher Tanja Petrushevska is leveraging the same datasets to search for strongly lensed supernovae, rare cosmic explosions whose light is bent and magnified by massive foreground galaxies, offering unique probes into the expansion of the universe and the nature of dark energy. The team’s involvement extends beyond observation, they are actively developing hydrodynamic simulations of tidal disruption events at the Centre for Astrophysics and Cosmology, modeling the debris fallback, stream self crossing, and accretion disc formation to provide theoretical frameworks that observers can use to extract black hole parameters from the incoming flood of data.
The scientific implications of this work are staggering. Astrophysicists estimate that the LSST will detect between 10 and 22 tidal disruption events per night, potentially discovering up to 80,000 such events over the decade-long survey, a monumental increase from the fewer than 100 currently known. These observations promise to revolutionize the census of supermassive black holes, particularly at the uncertain low-mass end of the distribution, while providing insights into accretion physics, stellar dynamics in galactic centers, and multi messenger astronomy, since some TDEs have been associated with high energy neutrinos and gravitational waves. The sheer volume of information, 7 million nightly alerts of celestial changes, requires artificial intelligence at every stage of analysis, making this project as much a computational revolution as an observational one. As Professor Gomboc emphasized, the collaboration stands on the threshold of major changes in astrophysics, where the vast amount of data and the AI driven methods needed to parse it are reshaping the discipline itself.
For Slovenia, this collaboration represents a remarkable integration into the highest tier of global astronomical research. The University of Nova Gorica’s participation through the European TALES and COFUND SMASH projects ensures that Slovenian researchers are not merely consumers of LSST data but active contributors to the theoretical and methodological frameworks that will define the survey’s scientific output. By combining access to the world’s most powerful sky mapping instrument with homegrown expertise in transient astrophysics and machine learning, the team is positioning the small Central European nation at the forefront of discoveries that could unravel the mysteries of dark matter, dark energy, and the violent lives of stars orbiting the universe’s most extreme objects.
