Final answer:
Stars, including our sun, are powered by nuclear fusion, where light atoms like hydrogen fuse to form heavier atoms and release energy, a process that occurs continuously in the sun's core at high temperatures.
Step-by-step explanation:
Every star, including our own sun, is powered by nuclear fusion. This is the process where the nuclei of light atoms, such as hydrogen, combine to form heavier atoms, like helium, while releasing a significant amount of energy. The sun can be envisioned as a vast sphere of hydrogen, with the gravitational pull being strong enough to overcome the repulsion between protons. In the sun's core, which has a temperature of about 14 million Kelvin, hydrogen nuclei merge to form helium. This process is continuous and releases energy in the form of photons, neutrinos, and other particles. If we compare this to another nuclear process, nuclear fission involves the splitting of heavy atomic nuclei into lighter ones to release energy. However, fission is not responsible for the energy produced by stars since stars contain predominantly light elements, which requires nuclear fusion for energy generation.