[violaine]

Joni Mitchell sang "we are stardust; we are golden. we are billion year old carbon"), is meant to imply more than that we are made of the same elements that stars are made of. Beyond that, the elements themselves (carbon, nitrogen, oxygen, etc.) were synthesized, cooked up as it were, in the nuclear furnaces that are the deep interior of stars. These elements are then released at the end of a star's lifetime when it explodes, and subsequently incorporated into a new generation of stars -- and into the planets that form around the stars, and the lifeforms that originate on the planets.

-- Michael Loewenstein and Amy Fredericks for "Ask an Astrophysicist"