So have you ever wondered why the Sun is in space - a zero-gravity, oxygen-free environment that can still burn brightly?
Fire is a chemical reaction that takes place in the presence of oxygen, in which energy is released in the form of heat, and at the same time carbon atoms combine with oxygen and produce carbon dioxide (CO2) gases. and carbon monoxide (CO), in addition, the hydrogen atom also combines with oxygen to form water. The burning reactions that people see every day on Earth is the burning of carbon, and it needs oxygen to maintain, when the oxygen runs out, the carbon burning process also stops.
However, the burning of the Sun is not a chemical combustion reaction as we know it, but rather a form of nuclear fusion. Nuclear fusion does not require oxygen, so the Sun does not burn using ordinary oxygen, but rather like a giant hydrogen bomb that burned brightly for billions of years.
In nuclear fusion, the nuclei of an atom fuse together to create new, larger nuclei. The structure and properties of an atom are determined by its nucleus, so when the nucleus changes, the atom will form a new element. For example, two hydrogen atoms combine to form a helium atom.
There are two main forces acting on the nucleus in a nuclear fusion reaction: electromagnetic repulsion and nuclear gravity. This reaction does not require the addition of other materials, but only heat or pressure large enough to help the nuclei overcome the electron repulsion to come closer to each other and bond together to form a new nucleus.
For example, the way to create high pressure and temperature in a nuclear bomb is to detonate other bombs. Or the way to create high pressure and temperature in a nuclear reactor is to insert electromagnetic waves or provide more high-energy particles.
As for nuclear fusion taking place in stars like the Sun, the high pressure and temperature created by the huge gravitational force. The fusion here takes place from the fusion of hydrogen with itself or with other light elements. Therefore, stars with enough mass to form strong enough gravitational forces would be able to form nuclear fusion.
This reaction will generate enormous thermal energy and be as luminous as our Sun today or the stars we can observe in the sky. The Sun has a surface temperature of more than 5000 degrees Celsius and the temperature in the core is about 16 million degrees Celsius, the pressure in the core is up to 25 trillion N/m2.
At the same time, it is the energy from the burning of stars that will continue to sustain their nuclear fusion until the helium in the core is burned out and collapses to become white dwarfs or stars. form a supernova if the star is large enough.
