What is Nuclear Fusion? | Fusion Power Explained | Nuclear Fusion Reaction in Sun | Dr. Binocs Show

Added: 2026-05-30

[00:00:10]Sticking those two same ends of magnets together is next to impossible, little kitty.

[00:00:17]>> Yeah. I just wanted to see what happens if I force them really close. Like what if they suddenly snap together and release energy?

[00:00:27]>> Oh wow, little kitty. That's actually a great way to begin understanding nuclear fusion, one of the most powerful processes in the universe.

[00:00:39]>> Really? What's that?

[00:00:41]>> Let's find out together by answering the question, what is nuclear fusion? Zoom in.

[00:00:50]At its core, nuclear fusion is the process by which two light atomic nuclei combine to form a heavier nucleus, releasing a huge amount of energy. This is exactly what powers the sun and other stars.

[00:01:09]Every second, the sun is fusing tiny hydrogen nuclei into helium, producing the light and heat that make life on Earth possible. But how does it actually work? Atoms are made of a central nucleus containing protons and neutrons surrounded by electrons.

[00:01:33]The key players in fusion are the nuclei especially those of hydrogen isotopes like dutarium and tritium. These nuclei are positively charged which means they naturally repel each other just like the magnets.

[00:01:52]So for fusion to happen we need to overcome this electrostatic repulsion.

[00:01:59]That's where extreme conditions come in.

[00:02:02]In the core of the sun, temperatures reach about 15 million° C and the pressure is unbelievably high due to gravity. Under these conditions, particles move incredibly fast. When hydrogen nuclei collide at such high speeds, they can get close enough for another force, the strong nuclear force, to take over. This force is much stronger than the repulsion, but it only works at very tiny distances. Once the nuclei are close enough, they snap together and fuse. When fusion happens, something interesting occurs. The mass of the new nucleus is slightly less than the combined mass of the original nuclei. That missing mass is not lost.

[00:02:57]It's converted into energy. According to Einstein's famous equation, E is equal to MC².

[00:03:07]Because the speed of light squared C² is such a huge number, even a tiny amount of mass produces an enormous amount of energy.

[00:03:20]On Earth, scientists are trying to recreate this process. But without the sun's gravity, we need other methods to achieve the same extreme conditions. One approach uses magnetic confinement where superheated gas called plasma is trapped using powerful magnetic fields inside a donut shaped device called doamac.

[00:03:49]Another method uses high powered lasers to compress and heat tiny fuel pellets in a fraction of a second. The biggest challenge is achieving something called ignition. The point where the fusion reaction produces more energy than it consumes. In December 2022, scientists made a major breakthrough in nuclear fusion. At a facility in the United States, they used powerful lasers to trigger a tiny fusion reaction that produced more energy than it used.

[00:04:28]Although the reaction lasted only a fraction of a second, it proved that controlled fusion is possible and brought us one step closer to using it as a real energy source. Despite the remaining technical challenges, fusion has incredible potential. It uses fuels like hydrogen which can be extracted from water and it produces very little long-term radioactive waste compared to nuclear fision which is a process of splitting heavy nuclei. If we can make it work efficiently, fusion could provide a nearly limitless clean source of energy. Trivia time. Did you know every atom in your body heavier than hydrogen was created inside the nuclear fusion furnace of a dying star billions of years ago?

[00:05:30]Yes, like the carbon in your muscles and the calcium in your bones are made of star stuff.

[00:05:38]It's sketching time. Today's sketch of the day goes to Ammoni Rataya.

[00:05:45]Hope you learned something really academic today. Until next time, it's me, Dr. Box, zooming out.

[00:05:56]So, Kitty, I hope you understand what nuclear fishision is.

[00:06:03]>> Um, I think they should call it nuclear confusion instead.

[00:06:10]>> Never mind.