To the untrained eye, the computer-generated aerial map shows only a triangle of red next to a field of blue. But the image produced by heat-sensing scanners developed by NASA is of a 17th-century Spanish mission.

"It's fantastic," said archaeology curator Jerry Milanich of the Florida Museum of Natural History. "I never saw anything so magical in my life."The scanners picked out what is left of the Mission Santa Fe de Toloco in a cow pasture dotted in spring with tiny purple flowers. Researchers have found what they believe are the kitchen, priests' residence, church and cemetery.

The Daedalus Multispectral Scanner, developed by the National Aeronautics and Space Administration's Space Remote Sensing Center, differentiate soil from clay and other early construction materials by differences in heat absorption.

The instruments will revolutionize archaeology, Milanich said, noting they saved $10,000 and five years' work. "If we started digging trenches, it would take forever, and we might destroy an important part of the site," he said.

The pasture - near the Santa Fe River in Alachua County north of the University of Florida Gainesville campus - is where missionaries tended crops, celebrated Mass and tried to spread the gospel to six nearby Indian villages.