10/15/2023

Scientists Have a Plan to Map the Ancient World Before it Disappears

It's audacious, and it just could work

In the center of Siena, Italy, a cathedral has stood for nearly 800 years. A black-and-white layer cake of heavy stone, fine-cut statuary, and rich mosaics, the imposing structure—now visited by more than a million tourists each year—would seem to be a permanent fixture of the city’s past, present and future. Most people call it, simply, "the cathedral." But Stefano Campana, a 53-year-old archaeologist at the University of Siena, calls it something else: "the church that is visible now."

Campana has seen his fair share of excavations, along with the dust and sunburns that accompany them. But archaeology, for him, is not always about digging up the past; it also means peering down into it using an array of sensitive electromagnetic equipment. One device Campana uses is ground-penetrating radar, which works by transmitting high-frequency waves into the earth to reveal "anomalies"—subsurface features that are potentially architectural—in the signals that bounce back.

In early 2020, when COVID-19 lockdowns emptied Italian tourist sites of their crowds, Campana and his collaborators received permission to survey the Siena cathedral's interior. Using instruments originally developed for studying glaciers, mines and oil fields, they spent days scanning marble floors and intricate mosaics, on the hunt for walls and foundations in the deep. With the selfie-stick brigade gone, Campana and his crew were able to find evidence of earlier structures, including, potentially, a mysterious church constructed there nearly 1,200 years ago, lurking like a shadow in the radar data.

Please select this link to read the complete article from WIRED.