Nuclear Fusion
NUCLEAR FUSION is the JOINING of light nuclei into a heavier one — releasing energy. The most common example: hydrogen → helium. Fusion powers the SUN and all stars. It produces FAR more energy per atom than fission and creates much less radioactive waste. The catch: fusion requires temperatures of ~100 million °C — hotter than the sun's core — to overcome the electric repulsion between protons.
Why fusion is hard. To fuse, two positive nuclei must get CLOSE ENOUGH for the strong force to take over. But they REPEL each other electrically. Only at extreme temperature/pressure do nuclei have enough energy to collide. The sun maintains fusion through its enormous gravity. On Earth, we use TOKAMAKS (donut-shaped magnetic confinement chambers) or LASERS (inertial confinement) to recreate fusion conditions. So far, fusion experiments cost more energy than they produce — but progress is real.
Why has not fusion been commercialized like fission?
The dream. Fusion would offer essentially unlimited clean energy. Fuel (deuterium from seawater) is abundant. Waste is minimal compared to fission. No risk of meltdown (the plasma cools and stops if anything goes wrong). If practical fusion is achieved, it could transform energy globally. Major projects: ITER in France (international tokamak), private companies (Commonwealth Fusion Systems, Helion), and NIF (laser fusion).
Sun Power
The sun fuses 600 million tons of hydrogen into helium PER SECOND. That is the energy source for all life on Earth. Practical fusion on Earth would essentially create artificial small suns.
Nuclear fusion is one of physics' greatest challenges and humanity's greatest energy possibilities. The race is on.
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