When did radiocarbon dating begin
Since the atmosphere is composed of about 78 percent nitrogen,2 a lot of radiocarbon atoms are produced—in total about 16.5 lbs. These rapidly combine with oxygen atoms (the second most abundant element in the atmosphere, at 21 percent) to form carbon dioxide (CO This carbon dioxide, now radioactive with carbon-14, is otherwise chemically indistinguishable from the normal carbon dioxide in the atmosphere, which is slightly lighter because it contains normal carbon-12.
Radioactive and non-radioactive carbon dioxide mix throughout the atmosphere, and dissolve in the oceans.
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.To measure the rate of decay, a suitable detector records the number of beta particles ejected from a measured quantity of carbon over a period of time, say a month (for illustration purposes).Since each beta particle represents one decayed carbon-14 atom, we know how many carbon-14 atoms decayed during that month.So if half the sand grains are in the top bowl and half in the bottom bowl, then 30 minutes has elapsed since the sand grains began falling.We can calibrate an hourglass clock by timing the falling sand grains against a mechanical or electronic clock.