Heading underground: Some 4.5 million kilograms of steel beams are set to be moved underground that will be used to hold neutrino detectors in place (Courtesy: Matthew Kapust, SURF). A vast complex of steel beams for a next-generation neutrino detector has begun its descent underground in what officials have called a “pivotal phase” towards construction of the $3.3bn Deep Underground Neutrino Experiment-Long-Baseline Neutrino Facility (DUNE-LBNF). An event was held yesterday – attended by senior officials including CERN director-general Mark Thomson and Dario Gil, undersecretary for science at the US Department of Energy (DOE) – to commemorate the start of moving 4.5 million kilograms of steel beams underground that will be used to hold DUNE’s detectors in place. I n February 2024 , excavation work finished on two huge underground spaces for DUNE.…