How old are the carbon atoms in our bodies?
Recently I read that carbon atoms on Earth are at least 6 billion years old (note: this question is not about the decay of isotopes).
How good are our astronomical and astrophysical models to determine this value? Could it be something like
6.6 billion years +/- 200 million ?
As far as I know, there are four important factors
1) metallicity of our sun
2) abundance of chemical elements in the universe versus in our solar system
3) shock wave impact mechanism on interstellar clouds of dust and gas
4) time requirements for the formation of our solar system
Many scientists seem to believe that at least two supernovae occurred after the big bang till our solar system was able to form.
What do we know about the timing? And the gaps between the supernovae and the formation of the solar system?
This question is in the General Section. Responses must be helpful and on-topic.