Satellite imagery obtained from NASA will help archeologist Bill Middleton of the Rochester Institute of Technology peer into the ancient Mexican past. Multi- and hyperspectral data will help build the most accurate and most detailed landscape map of the southern state of Oaxaca, where the Zapotec people formed the first state-level and urban society in Mexico.
Middleton's study will explore how the Oaxacan economy and environment changed as the Zapotec state grew and then collapsed into smaller city-states. The remote sensing technology works by differentiating materials on the ground on the basis of reflected light. Objects that look the same in visible light may have very different reflective properties when sampled across the spectrum.
Funding from NASA and National Geographic will also help Middleton build a picture of how climate and vegetation patterns have changed over time. Imagery from Earth Observing 1 and Landsat satellites, obtained over the last three years and covering 30,000 square kilometers, will help Middleton identify different plant` species, environments, ecosystems, and acres of arable land or mineral resources surrounding particular sites.