(CNN)The world’s biggest and most powerful physics experiment is taking place as you read this.
The Large Hadron Collider (LHC), a particle accelerator and the largest machine in the world, is ready for action following a two-year shutdown.
After problems that delayed the restart in March, scientists at the European Organization for Nuclear Research (CERN) completed final tests, enabling the first beams to start circulating Sunday inside the LHC’s 17 mile (27 km) ring.
“Operating accelerators for the benefit of the physics community is what CERN’s here for,” CERN Director-General Rolf Heuer said on the organization’s website. “Today, CERN’s heart beats once more to the rhythm of the LHC.”