CERN has crossed a major data milestone, storing one exabyte of experimental data generated by the Large Hadron Collider (LHC). The figure reflects more than 15 years of operations at the world’s most powerful particle accelerator, where billions of proton collisions per second produce vast streams of raw detector information.
Only a small fraction of this data reaches long-term storage. CERN relies on a highly selective trigger system that filters out most collision events in real time, retaining only the data with potential scientific value. That curated dataset feeds into CERN’s storage infrastructure, where physicists analyze results to test the Standard Model of particle physics and search for phenomena beyond it.
Long-term preservation remains central to CERN’s mission. Much of the exabyte is archived on magnetic tape, which offers low cost, high reliability, and decades-long data retention. As CERN prepares for the High-Luminosity LHC (HL-LHC), expected to begin operations around 2030, storage and processing demands are set to accelerate sharply.
- One exabyte equals one million terabytes of experimental data from LHC detectors
- Data accumulation reflects more than 15 years of collider operations
- Selective trigger systems discard the vast majority of raw collision data
- Magnetic tape serves as the primary medium for long-term data preservation
- High-Luminosity LHC is expected to generate roughly 10× more data than today’s LHC
“We’ve reached one exabyte, which is an impressive milestone, but it doesn’t end here. This is only 10% of what we will have to store and process in the next 10 years, so we have a huge challenge ahead,” said Jakub Mościcki, leader of CERN’s Storage and Data Management group.
