All the carbon atoms in the human body were created in the stars.

Elementary particles, such as protons, were formed during the "big bang"; that amazing moment about 14 billion years ago in which the universe got it's start. But, as the newly created universe rapidly expanded it also cooled, and cooled too quickly to allow the formation of atoms as large and complex as carbon. Their creation had to come later in a dying star.

Stars, like our own sun, generate all their vast quantities of radiation energy from simple hydrogen (a proton). At the unimaginable temperature of 100,000,000^o K, protons are crushed together with such force that the fuse to form the element Helium.

4¹H --> ⁴He

+ 2 positrons (anti-electrons) + 2 gamma rays + 2 electron neutrinos (one of three "flavor" of these elusive elementary particles).

+ 26.7 MeV (Million electron volts of energy)

(by comparison, a molecule on this planet has about 0.03 eV!)

As most stars age their supply of hydrogen is used up and the outside of the star begins to cool, changes color, expands and the star becomes a red giant. (Note: in about 5 billion years our sun will become a red giant, expand and consume the plants Mercury and Venus!).

The core of a red giant is compressed and compressed, until, at last, the forces are strong enough to begin fusing helium nuclei (called "alpha particles") together to form larger atoms such as carbon.

This is called the triple alpha process and can only occur in the center of a very dense star where the temperature is at least 100,000,000^o K.

⁴He + ⁴He --> ⁸Be

⁴He + ⁸Be --> ¹²C

+ 1 gamma ray

+ 7.275 MeV (Million electron volts of energy)

(As a continuation of this fusion process, one more alpha particle can now be crushed together with one of the carbon atoms to form an atom of oxygen, another important atom in living organisms).

All the carbon and oxygen in the human body, thus began in a dying star and are essentially the leftover ash from burning helium!