The primary component of the Sun is hydrogen, which accounts for about 74% of its mass. The Sun is primarily composed of a mixture of hydrogen and helium, with helium constituting approximately 24% of its mass. This vast composition of hydrogen allows for nuclear fusion to occur in the Sun's core, where hydrogen atoms fuse to form helium, releasing a tremendous amount of energy in the process. This energy is what powers the Sun's luminosity, providing the heat and light essential for life on Earth. The Sun’s fusion processes are fundamental to the Sun's life cycle and the stability of the solar system.