Lost in Time, Found by Satellites

摘要

Satellite data have revealed what may be buried pyramids and thousands of ancient settlements beneath Egypt's sands and farmlands. An American research team led by archaeologist Sarah Parcak of the University of Alabama, Birmingham, discovered the sites by analyzing data from visible as well as infrared satellite imagery. Parcak realized that winter rains soaking into buried mud-brick walls produced a subtle chemical signature in the overlying soil that showed up in high-resolution, infrared satellite images. Based on this clue and others, the team found traces of nearly 3000 ancient settlements and 1000 tombs. They also spotted 17 buried, pyramid-shaped structures; one at Saqqara, famed as a necropolis, was found to be an actual pyramid during a follow-up excavation.