This program explores the transformation of a secret military surveillance network into a crucial scientific tool for ocean exploration, and an anomalous feature of a certain part of the ocean that started it all.

During the Cold War, the U.S. Navy developed the Sound Surveillance System (SOSUS), using underwater hydrophones to detect Soviet submarines by listening to the ocean. This technology, originally designed for surveillance, has since been repurposed for scientific research.

The hydrophones that once monitored the oceans for Soviet submarine activity now form the keystone of the National Oceanic and Atmospheric Administration’s Sanctuary Soundscape Monitoring Project (SanctSound) and are vital tools to understanding marine life, monitoring earthquake an volcano activity, and enforcing nuclear test bans.

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