What is the process of nucleosynthesis?

Nucleosynthesis is the process of producing all chemical elements on a cosmic scale from one or two simple types of atomic nuclei. It involves large-scale nuclear reactions, similar to those occurring in the Sun and other stars.

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The process of forming new atomic nuclei from preexisting nucleons (protons and neutrons) is known as nucleosynthesis.

The Big Bang's quark-gluon plasma formed the primordial preexisting nucleons as it cooled to less than ten million degrees.

The genesis of nucleons in the universe may be referred to as nucleogenesis, the first process.

The process of nuclear fusion or fission is the main way that stars carry out the ensuing nucleosynthesis of the elements, which includes all forms of carbon, oxygen, and so on.

During a star's lifecycle, heavier elements are created from lighter ones through fusion and stellar nucleosynthesis, the process by which elements are formed through nuclear reactions in stars.