Discovery of carbon 14 dating
The second edition of Libby's , published by the University of Chicago Press in 1955, lists 27 pages of objects for which he had obtained radiocarbon dates before the fall of 1954.
"Libby's method remained the only way to measure carbon-14 in samples for several decades and was long considered the most accurate means of dating by carbon decay," said David Mazziotti, a UChicago chemistry professor who submitted the formal nomination of the site as a historic chemical landmark to the American Chemical Society.
But what's interesting is as soon as you die and you're not ingesting anymore plants, or breathing from the atmosphere if you are a plant, or fixing from the atmosphere. Once a plant dies, it's no longer taking in carbon dioxide from the atmosphere and turning it into new tissue. And this carbon-14 does this decay at a specific rate. And you say, hey, that bone has one half the carbon-14 of all the living things that you see right now.
And then you can use that rate to actually determine how long ago that thing must've died. It would be a pretty reasonable estimate to say, well, that thing must be 5,730 years old.
After one half life, it would have had 1/2 the carbon.
"Within 10 years of Libby's 1949 Radiocarbon dating is a key tool archaeologists use to determine the age of plants and objects made with organic material.
But new research shows that commonly accepted radiocarbon dating standards ...
By this means, scientists may date objects as much as 50,000 years old.
Minute radioactivity levels With his first graduate student, Ernest Anderson, and others, Libby determined that the expected minute level of radioactivity in organic material actually existed.