How does the sun produce heat and light energy?

Have you ever wondered that how the sun emits such tremendous amount of heat and light energy? Let’s know the science behind this huge ball of fire?

The Sun

The sun is a big ball of fire. The planets of the solar system revolve around the sun in a fixed elliptical orbit without coinciding each other’s orbit. It’s in fact the biggest among them such that the sum of masses of all the planets and satellite of the solar system is only equal to about 0.0015th part of the sun .

The mass of the sun is about 3*10^24 kg. The sun is composed of 74% of Hydrogen, 24% of Helium and 2% other elements. The surface temperature of sun is about 5700°c while the core temperature of the sun is about 1.5*10^7° c .Due to such high temperature everything is found in gaseous state. 

It emits about 2.7*10^24 kW energy every second which is extremely huge in general. But this entire emitted energy can’t reach the earth. The earth receives only 2.6*10^22 joules energy every second. Normally, about 1.4 kW of energy can be received by per square area of earth. This energy is also called Solar Constant.

The sun is also the ultimate source of energy because all the other forms of energy are basically derived from the sun. The sun gives off this much tremendous amount of heat energy via the process called “Nuclear Fusion”. Nuclear fusion reaction is the type of reaction in which lighter nuclei combines to form heavier nuclei under special conditions. Such types of reaction liberates extreme amount of heat energy.

Those conditions are:

a. High temperature

b. High Pressure

c. Abundant amount of Hydrogen gas

All these conditions are available on the sun which makes the nuclear fusion possible there.

The energy so liberated after the reaction is then radiated to the Space in the form of heat and light energy and the planets and other heavenly bodies receive it.

In nuclear fusion, a hydrogen atom is bombarded into protons (₁H¹)  and electrons under high temperature of about 10^8 K and the very high pressure of the sun binds the two nuclei (Protons) together though they have high repulsion to form an isotope of hydrogen (₁H²),deuterium. Again, the proterium and the deuterium isotopes of hydrogen combine to form a light isotope of Helium called ₂He³. Lastly, two light isotopes of Helium binds to form Heavy isotope of Helium i.e. ₂He⁴.The chemical reaction can be demonstrated as:  

This way the sun produces Heat and Light energy via the process of nuclear fusion.