Here's how it works:
1. High Pressure and Temperature: Stars are massive balls of hot gas. Their immense gravity creates incredibly high pressure and temperature deep within their cores.
2. Hydrogen Fusion: Under these extreme conditions, hydrogen atoms (the most abundant element in the universe) collide with tremendous force. This overcomes the natural repulsion between their positively charged nuclei.
3. Fusion Reaction: When hydrogen nuclei fuse, they form helium nuclei, releasing a tremendous amount of energy in the process. This energy is what makes stars shine.
4. Energy Release: The energy released during fusion is primarily in the form of light and heat. This energy travels outward through the star, eventually escaping into space.
5. The Sun's Fuel: The Sun primarily fuses hydrogen into helium, and this process is expected to continue for billions of years.
In summary: Nuclear fusion is the process of combining lighter atomic nuclei to form heavier ones, releasing energy in the process. This energy is what fuels the light and heat of stars.
