system
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human
ELI5 Carbon dating

Please explain carbon dating to me.
gpt
Carbon is plentiful in every living (and therefore dead) thing.  So people, object made from natural fibers, etc...all have carbon in them

There are a few different types of carbon.  One is stable (Carbon-12) and one is unstable (Carbon-14).  The unstable Carbon slowly decays and becomes Nitrogen as it is affected by the environment.  However, it is constantly being replenished as you eat or otherwise live.

So once something dies, or ceases to exist in a normal state, the Carbon-14 no longer replenishes itself, only decays.  So we compare the amount of Carbon-12, with the amount of Carbon-14 left in the object and compare that with the known rate of decay for Carbon-14.  How much has decayed tells us how long it has been decaying, and therefore how long it has been since something died.