Beneath the reflective surface of the world’s oceans lies a landscape more rugged and dramatic than any terrestrial mountain range. For centuries, humanity charted these waters using lead lines and single-beam echoes, retrieving mere pinpricks of data from a vast dark canvas. The advent of multibeam sonar mapping transformed this primitive sketch into a high-definition portrait. By emitting a fan-shaped array of sound pulses across a wide swath perpendicular to a vessel’s path, this technology captures thousands of depth points simultaneously. Instead of a thin line of data directly below the ship, hydrographers now receive a complete corridor of seafloor…