Wiki carbon 14 dating
The ratio of normal carbon (carbon-12) to carbon-14 in the air and in all living things at any given time is nearly constant.
Maybe one in a trillion carbon atoms are carbon-14.
The carbon-14 atoms are always decaying, but they are being replaced by new carbon-14 atoms at a constant rate.
At this moment, your body has a certain percentage of carbon-14 atoms in it, and all living plants and animals have the same percentage.
Carbon-14 is radioactive, with a half-life of about 5,700 years.
For more information on cosmic rays and half-life, as well as the process of radioactive decay, see How Nuclear Radiation Works.
Since dinosaurs are thought to be over 65 million years old, the news is stunning - and more than some can tolerate.
Critics charged that the findings were mistaken or that what she called soft tissue was really biofilm produced by bacteria that had entered from outside the bone.
Schweitzer answered the challenge by testing with antibodies.
It's accuracy has been verified by using C-14 to date artifacts whose age is known historically.
The fluctuation of the amount of C-14 in the atmosphere over time adds a small uncertainty, but contamination by "modern carbon" such as decayed organic matter from soils poses a greater possibility for error. Thomas Seiler, a physicist from Germany, gave the presentation in Singapore.