Missouri State University Research Archaeologist Christopher Bodine recently presented his work at the “NASA and Archaeology from Space” symposium, held Sept. 18-19 at NASA’s Space Rocket Center in Huntsville, Alabama.

Bodine, who works at the Bernice S. Warren Center for Archaeological Research, presented “Airborne Synthetic Aperture Radar (AIRSAR): SAR Data for Detection and Preservation in North American Archaeological Contexts.”

Symposium attendees came from a diverse range of organizations and institutions, Bodine noted. These included NASA, the National Laboratories system, UNESCO, North American and European universities and private industries.

Many of these individuals have been essential in developing and applying arial remote sensing techniques in archaeology, he added.

Using AIRSAR technology to evaluate Cahokia Mounds

Bodine focused his research on the Cahokia Mounds near St. Louis, Missouri. His goal was to “determine the current and future potential of SAR datasets to highlight the geometric features caused by human-soil interactions at Cahokia.”

“The archaeological site of Cahokia Mounds is the largest Mississippian site and the largest archaeological site north of Mexico City,” Bodine explained. “At one time upwards of 30,000 people resided within Greater Cahokia.”

Exploring the potential of SAR datasets, he noted, adds new tools for researchers and archaeologists to identify and preserve other unknown archaeological features and sites in North America.

SAR technology a viable option

Bodine’s research explored legacy data from May 1999, when NASA conducted a test of airborne synthetic aperture radar (AIRSAR). He used AIRSAR technology to analyze different radar bands collected over the Cahokia Mounds.

“Three SAR bands collected over one site like Cahokia at the same time is extremely rare and provides a unique opportunity to test this technology,” Bodine said.

AIRSAR was a prototype sensor designed and built by the jet propulsion laboratory (JPL) earth-observation project. It was used as an all-weather imaging tool able to penetrate through clouds and collect data at night, according to the Alaska Satellite Facility, which hosts the data.

SAR technology is a powerful but complicated form of remote sensing that archaeologists can use, according to Bodine. Interpretation and processing require specialized training and expertise as well as significant computing resources, he added.

Algorithms reveal unique signatures at Cahokia

Bodine applied edge and line detection algorithms to highlight geometric features within the Cahokia Mounds.

“When you apply these algorithms to the imagery, you can see the area around the main plaza appears darker than the surrounding landscape,” he explained. “This is notable because during the height of occupation at Cahokia there were four plazas situated around Monks Mound.”

In addition, the technology revealed other types of image signatures west of the central plaza. These signatures are not apparent using other sensor imagery or to the naked eye, Bodine said.

Bringing national attention to CAR’s work

Bodine said the symposium presented an excellent opportunity to learn about the latest advancements in geospatial archaeology. Moreover, Bodine was able to showcase ongoing research at Missouri State.

“I had several discussions about possible future projects and funding opportunities that could benefit CAR and lead to more national and international exposure,” he said.

Bodine said his presentation has already led to a new research partnership with scientists at the NASA Jet Propulsion Laboratory. One goal of the partnership is to identify future avenues for research and funding using arial remote sensing and NASA resources.

“I was just happy for the opportunity to help grow the profile of CAR and MSU,” Bodine said. It is a subject he and colleagues, including CAR Director Kevin Cupka Head, discuss frequently.

“How can we build on what CAR has already done and reach even higher?” Bodine asked. “CAR and MSU are in a unique and excellent position to produce cutting-edge research and draw national and international attention.”

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