GPS turns military precision into everyday dependence

The brief

Katherine Dunn begins with the wonder of early GPS, then turns to its vulnerability: jamming and spoofing have made satellite navigation a cat-and-mouse game.

GPS works by comparing signals from multiple satellites to calculate location, altitude, and precise timing. The system is powerful, but interference can corrupt the answer.

Dunn traces GPS to military needs in World War II, the Cold War, and Vietnam, with space-race research supplying crucial scientific foundations.

A standout thread is Gladys West’s mathematical work modeling Earth’s gravitational field and satellite trajectories, a largely hidden foundation of modern navigation.

The episode also corrects a common privacy misconception: GPS itself receives signals one way; tracking begins only when another device or service transmits location data.