Category: Smelting



All of us are made of star stuff but it takes a special star to make iron. It takes a really big star. Much, much bigger than our Sun. The main source of energy in any star, our sun included, comes from the nuclear fusion of hydrogen into helium at the core. The radiation  pressure from these reactions resists the enormous gravity of the outer shell preventing collapse. There is not an unlimited supply of hydrogen in the core however. At some point as fuel runs out the core cannot resist the pressure of the outer shell.

What happens next

A star such as our sun will eventually grow into a Red Giant, convert the helium in the core to carbon, then nova or explode its outer shells into nebulae. The carbon in the core will glow white from the retained heat making a white dwarf that will eventual cool into a black dwarf about the size of the earth. Pretty tame stuff. Except for the fact if it were our sun it would obliterate all life on our planet.

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