Illustrated · 1 min
Heavy Elements
As you probably know, stars "burn" because they release large amounts of energy when hydrogen fuses to form helium and heavier elements such as carbon.
When two hydrogen atoms collide and produces energy, this marks the beginning of nuclear fusion. The result is two subatomic particles, neutrinos and positrons, as well as an atom of helium. Depending on the mass of the star, it can fuse larger atoms and form elements as heavy as iron.
Nuclear fusion over time.
Honestly, this diagram explains it all for you.