The prodigious mobilization of science that produced nuclear weapons was so far-reaching that it revolutionized even the study of ancient climates.
Nuclear laboratories, awash with funds and prestige, spun off the discovery of an amazing new technique radiocarbon dating.
One application was a timetable of climate changes for tens of thousands of years back.
Making the job harder still, baffling anomalies turned up.
The carbon-14 dates published by different researchers could not be reconciled, leading to confusion and prolonged controversy.
Comparing the old wood with modern samples, he showed that the fossil carbon could be detected in the modern atmosphere.(5) Through the 1950s and beyond, carbon-14 workers published detailed tables of dates painstakingly derived from samples of a wondrous variety of materials, including charcoal, peat, clamshells, antlers, pine cones, and the stomach contents of an extinct Moa found buried in New Zealand.(6) The measurements were correlated with materials of known dates, such as a well-documented mummy or a log from the roof of an old building (where tree rings gave an accurate count of years).
The results were then compared with traditional time sequences derived from glacial deposits, cores of clay from the seabed, and so forth.
The radioactive isotope carbon-14 is created in the upper atmosphere when cosmic-ray particles from outer space strike nitrogen atoms and transform them into radioactive carbon.
Some of the carbon-14 might find its way into living creatures.
This was all the usual sort of laboratory problem-solving, a matter of sorting out difficulties by studying one or another detail systematically for months.
More unusual was the need to collaborate with all sorts of people around the world, to gather organic materials for dating.
Also, the Sun’s own magnetic field varies with the cycle, and that could change the way cosmic particles bombarded the Earth.