Word: carbonizing
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Photographing Deimos. There was disagreement about the composition of the glaciers. Carl Sagan, director of Cornell University's Planetary Studies Lab, suggested that the glaciers are frozen carbon dioxide (dry ice), the major constituent of the polar cap. Smith felt that dry ice would not flow like a glacier. "The only thing that does," he said, "is water." Mariner's instruments did detect water vapor in the atmosphere above the south polar cap, suggesting that it had risen from the ice below. Those readings encouraged scientists who still hope to find some form of ife, however rudimentary...
...actual historical records to date from only 2500 B.C. But except for a few iconoclastic prehistorians like Britain's Colin Renfrew of Sheffield University, most archaeologists remained thoroughly convinced "diffusionists." If a few prehistoric European monuments or artifacts happened to show unusual antiquity, they contended, it was the carbon 14 clocks that were in error, and not their well-entrenched ideas...
...debate is rapidly being resolved. When Libby first proposed carbon 14 dating in 1950, he assumed that the total world supply of the isotope was about the same as it had been in the past. Reason: carbon 14 is being produced continuously in the atmosphere as cosmic rays bombard the earth from deep space and leave a trail of atomic debris. But as the number of puzzling carbon 14 dates increased, scientists at the universities of Arizona, Pennsylvania and California began testing Libby's assumption by turning to some of the oldest living things on earth-California...
Before the Pyramids. Working with hundreds of ancient wood samples, Geochemist Hans Suess of the University of California at San Diego recalibrated archaeological ages derived by carbon 14 dating in all parts of the world. His corrections did not affect the commonly accepted dates of Near East events and artifacts, which have been largely deduced from ancient calendars. But they did show that carbon-14-based European dates before 1500 B.C. must be adjusted by the addition of as many as 700 years...
...adjustments have already stirred what Renfrew calls a major revolution in archaeological thinking. Brittany's tombs, for example, are now acknowledged to have been built at least a millennium before the first stone tombs in the eastern Mediterranean and 1,500 years before the first pyramids. The revised carbon 14 dates have also shown that skilled coppersmiths may have been at work in the Balkans and possibly prehistoric Spain even before the Greeks managed to master the metallurgical arts. "The central moral is inescapable," Renfrew recently wrote in Scientific American. "We have completely undervalued the originality and creativity...