When did radiocarbon dating begin
After all, we should be able to estimate how long ago a creature lived based on how much radiocarbon is left in its body. Radiocarbon (carbon-14) is a very unstable element that quickly changes into nitrogen.
Half the original quantity of carbon-14 will decay back to the stable element nitrogen-14 after only 5,730 years.
The difference in the number of sand grains represents the number of carbon-14 atoms that have decayed back to nitrogen-14 since the mammoth died. The sand grains in the top bowl fall to the bottom bowl to measure the passage of time.
Because we have measured the rate at which the sand grains fall (the radiocarbon decay rate), we can then calculate how long it took those carbon-14 atoms to decay, which is how long ago the mammoth died. If all the sand grains are in the top bowl, then it takes exactly an hour for them all to fall.
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.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.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.