Nuclear Fusion Explained

☀️ Nuclear Fusion Explained

Nuclear fusion is the joining of two small, light nuclei to form a larger nucleus. The mass of the products is slightly less than the mass of the reactants — and this tiny mass difference is converted to an enormous amount of energy via E = mc².

Fusion powers the Sun and all stars. In the Sun, hydrogen nuclei (protons) fuse together to form helium, releasing energy as light and heat. On Earth, experiments use deuterium and tritium (isotopes of hydrogen) which fuse more easily and release 17.6 MeV per reaction.

The challenge is that nuclei are positively charged and repel each other strongly. To overcome this repulsion, they must be heated to over 100 million °C so they move fast enough to get very close. At these temperatures, matter exists as a plasma — no container material can hold plasma, so magnetic fields are used instead (tokamak reactors).