FROM a flint hand axe dating back to the early Ice Age to Oman's
lost city of frankincense (see story Page 13), archaeologists are
finding ancient artifacts by studying pictures of the earth taken
from space. Using remote-sensing techniques to aid their research,
scientists have uncovered treasures hidden underground for
thousands of years.
"Remote-sensing is just seeing from afar," says James Wiseman,
chairman of the Boston University (BU) Department of Archaeology,
who employed this technology in a project near Preveza, Greece.
"It is an instrument that we use to discover things without
having to see or touch them," says Farouk El-Baz, director of the
Center for Remote Sensing at BU. The technique is useful in
archaeology, he says, because it provides detail over a large area
and at great depth. A remote sensor on a satellite can take images
from 570 miles above the earth. Because the sensor is actually a
multispectral camera that uses the electromagnetic spectrum (energy
waves) to detect objects, artifacts buried as deep as 30 feet below
the surface can be found. The electromagnetic spectrum includes
energy waves from infrared, visible or ultraviolet light, X-rays,
and radio waves.
"Images taken through remote-sensing show evidence of previous
human habitats by depicting patterns of civilization such as the
remains of cemeteries, abandoned roads, or dry river beds" that are
presently covered with sand, soil, or water, says Dr. El-Baz. "The
electric current given off picks up anything that is different from
the existing soils."
Smaller scale remote-sensing instruments suspended from
aircraft, blimps, or even a scientist's hand can be used to zoom in
Dr. Wiseman's project makes use of all the types of
remote-sensing instruments. The project covers 400 square
kilometers (154 miles) of terrain, from the Ambracian Gulf to the
Adriatic coast and a time period of several thousand years.
"We're looking at piecing together the cultural history of the
ancient city of Nikopolis in Epirus, Greece, and explaining the
changing relationships, from prehistoric through medieval times,
between the people that lived there and the land they inhabited,"
"Using remote-sensing," he continues, "We can research a project
the size of ours and have results within three to five years.
Before, it would take three generations of archaeologists to walk
the area, make observations, dig a little here or there, and hope
that they found something.
Last summer, a member of Wiseman's group, Curtis Runnels,
uncovered an Acheulean hand axe. This axe, named after the French
city of St. Acheul where the first one was found, is evidence that
ancestors of modern humans inhabited the Greek peninsula during the
Lower Palaeolithic period of the early Ice Age, some 200,000 to
500,000 years ago. …