The Big Bang gave us hydrogen, helium and a fraction of lithium. All the other elements in nature - the iron in our blood, the calcium in our bones and the gold in our jewelry - were synthesized inside stars that lived and died millions or even billions of years ago. In other words, the nature and extent of the synthesis of elements over the history of the Universe has changed with time and stellar evolution. Yet one aspect of stars has altered very little over billions of years, and of light years: the relative abundance patterns of certain heavy elements. These are consistent all the way through, from the Methuselahs of the star world to infants such as our Sun.
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