Stellar nucleosynthesis is the collective term for the
nuclear reactions taking place in
stars to build the nuclei of the heavier
elements. (For other such processes, see
nucleosynthesis.)The processes involved began to be understood early in the twentieth century, when it was first realised that the
energy released from nuclear reactions accounted for the longevity of the
Sun as a source of
heat and
light. The prime energy producer in the sun is the
fusion of
hydrogen to
helium, which occurs at a minimum temperature of 3 million
kelvin.
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