Early-career physicist Jonathan LeyVa helps build one of the world’s most sensitive dark matter detectors. LeyVa works in a clean room at the Department of Energy's SLAC National Accelerator Laboratory, where crews are building detectors for the latest in a series of Super Cryogenic Dark Matter Search (SuperCDMS) experiments. As an early-career physicist, part of his job is keeping track of how much exposure to cosmic rays—high-energy particles falling in from space—the detector components are getting. Researchers want to keep that exposure to a minimum because it could harm their ability to detect dark matter later on.