The Atlantic Neutrino Surveillance System (codename System 12, originally Project 906) is a covert federal system in Vekllei that detects nuclear reactors worldwide by measuring the neutrinos they produce. Deep underground detector arrays in mines and volcanic caverns across Vekllei’s republics monitor the constant flux of antineutrinos emitted during fission and fusion, identifying individual reactor facilities by their energy spectra and locating them by triangulating arrival directions across multiple stations.
The system emerged in the 2050s from particle physics research conducted by the NSRE, which recognised that its neutrino detector installations – built for legitimate scientific purposes – could simultaneously track reactor operations around the world. Neutrinos pass through the Earth essentially unimpeded, so no amount of concealment or shielding can hide a running reactor from a sufficiently sensitive detector. The intelligence value was obvious, and classified analysis was layered onto existing scientific programs without most researchers knowing about it.
The primary System 12 installation occupies a “deep site” in a former mine shaft in Kala known as the Deep Particle Observatory, where overlying rock filters out cosmic ray interference. System 12 shares the Deep Particle Observatory with System 11. Each detector comprises thousands of tonnes of purified water monitored by photomultiplier tubes that register the faint light produced when a neutrino interacts with detector material – an extraordinarily rare event, but one that occurs often enough at scale to produce usable data. The detectors record neutrino energy and direction, and System 3 correlates readings across stations to build a constant picture of reactor activity worldwide.
What makes the system particularly useful in the Atlantic is the prevalence of monopolar reactors like Vekllei’s own MMR-III. Many commercial vessels and a growing number of aircraft operating around the world use compact fission and fusion reactors for propulsion, each producing a characteristic neutrino signature during operation. The result is that System 12 tracks not just military submarines and foreign naval vessels but much of the routine shipping and air traffic transiting the Atlantic. Combined with acoustic data from the Atlantic Hydrographic System and seismic readings from the Seismic Intelligence System, the neutrino network gives the Commonwealth an unusually complete picture of what moves through its oceanic territories.
The system operates under cover of fundamental physics research, and the NSRE publishes genuine scientific results from the same detectors. Most personnel conduct real particle physics; the classified reactor monitoring uses separate analysis of the same data, compartmentalised from the scientific staff. As such, many in the NSRE are aware that some kind of neutrino surveillance is occurring but are not privy to its scale or use.