As you learned in the previous page, carbon dating uses the half-life of Carbon-14 to find the approximate age of certain objects that are 40,000 years old or younger.In the following section we are going to go more in-depth about carbon dating in order to help you get a better understanding of how it works.
Through photosynthesis carbon dioxide enters plants and algae, bringing radiocarbon into the food chain.Radiocarbon then enters animals as they consume the plants (figure 2).When these energetic neutrons collide with a nitrogen-14 (seven protons, seven neutrons) atom it turns into a carbon-14 atom (six protons, eight neutrons) and a hydrogen atom (one proton, zero neutrons).Since Nitrogen gas makes up about 78 percent of the Earth's air, by volume, a considerable amount of Carbon-14 is produced.Radiocarbon (carbon-14 or C) forms continually today in the earth’s upper atmosphere.
And as far as we know, it has been forming in the earth’s upper atmosphere at least since the Fall, after the atmosphere was made back on Day Two of creation week (part of the expanse, or firmament, described in Genesis 1:6–8). Cosmic rays from outer space are continually bombarding the upper atmosphere of the earth, producing fast-moving neutrons (sub-atomic particles carrying no electric charge) (figure 1).1 These fast-moving neutrons collide with nitrogen-14 atoms, the most abundant element in the upper atmosphere, converting them into radiocarbon (carbon-14) atoms.
date of organic material - but an approximate age, usually within a range of a few years either way.
The other method is “Relative Dating” which gives an order of events without giving an exact age (1): typically artefact typology or the study of the sequence of the evolution of fossils.
So even we humans are radioactive because of trace amounts of radiocarbon in our bodies.
After radiocarbon forms, the nuclei of the carbon-14 atoms are unstable, so over time they progressively decay back to nuclei of stable nitrogen-14.3 A neutron breaks down to a proton and an electron, and the electron is ejected. The ejected electrons are called beta particles and make up what is called beta radiation. Different carbon-14 atoms revert to nitrogen-14 at different times, which explains why radioactive decay is considered a random process.
Libby and coworkers, and it has provided a way to determine the ages of different materials in archeology, geology, geophysics, and other branches of science.