"The Cosmos was originally all hydrogen and helium. Heavier elements were made in red giants and in supernovas and then blown off into space, where they were available for subsequent generations of stars and planets. Our Sun is probably a third-generation star. Except for hydrogen and helium, every atom in the Sun and the Earth was synthesized in other stars. The silicon in the rocks, the oxygen in the air, the carbon in our DNA, the gold in our banks, the uranium in our arsenals were all made thousands of light-years away and billions of years ago. Our planet, our society and we ourselves are built of star stuff."

Carl Sagan (cosmos series, the lives of the stars)