The most abundant element in the sun is hydrogen, making up about 74% of its total mass. Hydrogen is the primary fuel for the nuclear fusion processes occurring in the sun's core, where it is converted into helium through a series of reactions. This fusion process releases tremendous energy, which ultimately powers the sun and provides light and heat to our solar system. Following hydrogen, helium is the second most abundant element in the sun, constituting around 24% of its mass. Other elements, such as oxygen, carbon, neon, and iron, exist in trace amounts, but hydrogen remains the dominant element.