The Big Bang made mostly hydrogen and helium. Almost every other element in your body, from the carbon in your cells to the iron in your blood, was forged inside stars and scattered when they died.
Truth label: Established. Strong evidence and broad agreement among experts.
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Star furnaces
Stars fuse light elements into heavier ones in their cores, all the way up to iron.
Explosions do the rest
Supernovae and star collisions create heavier elements and spread them through space.
Learn
- Recycled. The Sun and Earth formed from gas and dust left by earlier generations of stars.
Test yourself
Where was most of the iron in your blood made?
Inside stars. Iron is forged in the cores of massive stars.
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