Nuclear fusion is the primary reaction occurring in the Sun's interior, facilitated by extreme conditions.
Nuclear fusion is the reaction that takes place in the interior of the Sun, where hydrogen atoms combine to form helium, releasing a tremendous amount of energy. This process occurs in the Sun's core, where the extreme temperature and pressure allow for fusion reactions to happen.
In contrast, nuclear fission involves the splitting of heavy atomic nuclei into smaller ones, which is not the primary process in the Sun's interior.
Plasma, which is a state of matter consisting of charged particles, particularly electrons and ions, woven with magnetic fields, is what constitutes the Sun's interior, where nuclear fusion reactions occur.
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