When Popocatépetl speaks,
let Mexico hear it in time.

A country that knows the cost of no warning.

In 1985 an earthquake changed Mexico forever. Popocatépetl keeps up frequent explosive activity — a strong, near-daily signal — and 22 million people live in its shadow. The Pacific coast lives with tsunami risk. The same idea that inspired HERD — the animals that sensed the 2004 tsunami — applies here too, and today, for the first time, sensors are cheap enough to deploy it at scale.

Conceptual image — communities in the shadow of Popocatépetl, with the listening network drawn over the sky.

Born in Phuket, in memory of December 26, 2004. Mexico is our first step in Latin America.

One sensor hears noise. A hundred thousand hear the volcano.

A single cheap barometer can't tell an explosion 70 km away from a slamming door. But when thousands of sensors catch the same low-frequency signature, with the right delays across geography, the noise cancels and the signal emerges. That's how Google turned ordinary phones into a global earthquake detector. Our bet: do it with infrasound.

The cheap sensor network →

Conceptual image of the planned coverage — not a real network yet.

We don't ask for faith. We give you the sources.

We gathered what science knows about infrasound into an open library, each article with its own bibliography. Here are the facts behind every claim on this page.