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Energy of the sun

How does the sun get all its energy ?

energy of the sun

Fusion Reaction

The energy of the sun in form of The heat that we feel is emitted from its surface which is over 6000 degrees Celsius. This temperature is not hot enough for fusion reaction to take place though, so when moving deep down into the core   of the sun the temperature and pressure are higher enough for fusion reactions to take place. At the sun’s core there is a dense hydrogen plasma which is a mixture of electrons and protons. The protons are the particles that we’ll focus on. They bounce around with tremendous force but they don’t want to collide with each other because positive charges repel, so, when two protons get close, the repulsion makes them swerve apart. The closer they come together, the stronger the repulsion gets. These protons really don’t want to be close to each other. But so often, because of the massive heat and the enormous speed of protons, they hit each other in a head-on collision which will force them very close together and a new force will come into play which called the strong nuclear force, it only works over short distances 
but, get two protons close enough together, and this force can overcome the repulsion caused by their positive charges.

The protons are pulled together at which point something weird happens. One of these protons emits two smaller particles. The first one is a neutrino, a tiny particle that moves at almost the speed of light. These particles which are emitted deep in the core of the sun, just stream out into space never to be seen again. The proton also emits a second particle which is the anti-electron, this is the anti-version of an electron which normally has a negative charge, this positron has a positive charge.

This particle carries the positive charge away and so the proton, having lost its electrical charge, becomes a neutron. It’s a process called Beta Plus decay and this is how the neutrons in helium get formed. Note that the helium is an atom formed with one proton and one neutron in its nucleus.

No. 3246: Helium, The Up-Lifting Element

After this step we have a proton and a neutron joined together, this is a heavy form of hydrogen called deuterium. This deuterium nucleus will move around in the sun’s core with all the other particles, but it will have another encounter very quickly. Within one second, it will have a head-on collision with another proton   and they will come together with enough force for the next fusion event to take place. The strong nuclear force will once again work its magic and the proton and the deuterium will be pulled tightly together to form a new nucleus containing two protons and one neutron. This is a light form of helium called helium-3.

When this fusion takes place, it emits a powerful gamma ray which is absorbed by the surrounding plasma and add heat to the sun’s core. The helium-3 nucleus that was produced move around in the dense solar plasma with the other particles until eventually it meets another helium-3 nucleus. If they meet with the needed force, the final fusion event occurs. Once the nuclei are close enough, the strong 
nuclear force takes over and pulls them together. Now there is six particles pulled together but this final fusion event ejects two of the protons from the newly formed nucleus. Being fired back into the plasma with huge force, they add yet more heat into the sun’s core and they will get reused in further fusion events.  

The nucleus that remains consists of two protons and two neutrons, known as helium-4.   This helium is the final end result of the fusion reactions that have taken place. But there’s a missed particle we still need to talk about: the electrons. The fusion reactions shown here fused four hydrogen nuclei into one nucleus of helium. Each of these hydrogen nuclei had an associated electron, so four electrons in total. A helium atom, though, only has two electrons so we have two electrons left over. Ones that used to belong to hydrogen atoms but have no place in the new helium atom.  

What happens to these leftover electrons?

Remember those anti-electrons (Positron) from the first stage of fusion, they will quickly collide with the leftover normal electrons and, when a particle and an anti-particle meet, they emit a flash of gamma radiation and then they will disappear. The particles are annihilated 
leaving nothing behind. And the gamma-ray   flash that was produced when they met adds 
even more heat into the core of the sun.   And so those leftover electrons have vanished 
and we’ve balanced the books.

This is how in the sun there is a fusion of four hydrogen atoms into one atom of helium and it does this a hundred billion billion billion times per second and has been doing so for the last five billion years. The heat produced by this fusion process goes to the surface of the sun and, after an eight minute journey through space, provides the Earth with its daylight and its warmth.

Energy of the sun