The KM3NeT telescope comprises two detectors, ARCA and ORCA, utilizing seawater to capture Cherenkov light—a bluish glow produced when neutrinos interact with water molecules.

Using an observatory under construction deep beneath the Mediterranean Sea near Sicily, scientists have detected a ghostly subatomic particle called a neutrino boasting record-breaking energy in another important step toward understanding some of the universe's most cataclysmic events.