Iron peak
The nuclear binding energy of the elements (the energy holding the nucleus together, or the energy required to split the nucleus) increases from Hydrogen upwards through the lighter elements and peaks at Iron, where it then starts to decrease.
In other words, for elements up to iron, nuclear fusion releases energy and after iron nuclear fusion consumes energy. So the elements up to iron can be created in stars (stellar nucleosynthesis) whereas the elements heavier than iron need the much higher energy of a supernova to form (supernova nucleosynthesis).
This soup of elements knocks around the universe for a few billion years then coalesces into stuff like galaxies, planets, you, me, your iPhone, the cat, etc
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Raving Homasecsyouall the hours are good but the work sucks, Tue 13 Mar 2012, 17:08,
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