Final answer:
The major components of the sun are hydrogen and helium. Hydrogen, which comprises about 73% of the Sun's mass, fuels nuclear fusion reactions that convert hydrogen to helium, making up 25% of its mass.
Step-by-step explanation:
The major components of the sun are hydrogen and helium. Hydrogen serves as the main fuel for the Sun's nuclear fusion reactions, where hydrogen nuclei (protons) fuse to form helium, attributing to about 73% of the Sun's mass. The remaining mass is primarily helium, constituting about 25%, and less than 2% is made up of other elements such as carbon, oxygen, and nitrogen.
The Sun operates through what is known as the proton-proton chain reaction, which dominates in stars the size of the Sun or smaller. The fusion of hydrogen atoms occurs in the core of the Sun, where 620 million metric tons of hydrogen are converted into helium each second. This process releases an immense amount of energy, which we perceive as sunlight. The Sun, being a main-sequence star, is quite typical of stars in general, with its outer layer having a different composition from Earth's crust. While the top three elements in Earth's crust are oxygen, silicon, and aluminum, the Sun's atmosphere is vastly composed of hydrogen and helium.