There is a reason that Earth is the only place in the solar system among the Sun and its planets, where life is able to live and thrive. Granted, scientists believe that there may be microbial or even aquatic life forms living beneath the icy surfaces of Europa and Enceladus, or in the methane lakes on Titan. But for the time being, Earth remains the only place that we know to have all the right conditions for life to exist.
One of the reasons for this is because the Earth lies within our Sun’s Habitable Zone. This means that it is in right spot (neither too close nor too far) to receive the Sun’s abundant energy. This includes the light and heat that is essential for chemical reactions. But how exactly does our Sun go about producing this energy?
On top of all that, how does the Sun keeps itself together from shrinking itself due to its own gravity? Earlier, scientists believed that there must be a force in the Sun (stars) against its own gravity to prevent it from shrinking due to its own gravity. But it raised an important question. What mechanism can generate such a force? It obviously does not appear out of thin air!
In 1899 T. C. Chamberlin suggested that the reactions between nuclei of atoms might cause the generation of energy need for such a counter force. But he didn’t have any explanation about it. Later, the greatest scientist of all the time, Albert Einstein put forward the theory that the mass of a body can turn into energy. Hence he provided light to this mystery by formulating the well-known equation,
E = m c2 where; E = Energy produced
m = Mass which turned into energy
c = Velocity of light
To put it in a simple way, according to this equation, 1g of mass is sufficient to produce energy which is almost equivalent to energy released by 20 kilo tons of TNT. Isn’t it amazing?
After that, A.S. Eddinton showed that the conversion of Hydrogen into Helium will provide energy to power the sun. But his theory lacked necessary details. In about 1905, it was found that sun generates energy inside it by a process called “Nuclear Fusion”; where 2 or more nuclei bind together to form a single nucleus. Fusion of Hydrogen atoms into Helium atoms occur under 3 steps called “proton-proton chain”. It can be summarized as below.
1H + 1H → 2H + e+ + υ
2H + 1H → 3He + γ
3He + 3He → 4He + 2 1H
Here e+ denotes a positron and υ denotes a neutrino which are smaller than a sub atomic particle. If we observe the above mentioned steps, we can predict that 4 Hydrogen atoms get fused into a Helium atom. But there’s a difference between the mass of 4 Hydrogen atoms and that of Helium atom. That mass is said to be converted into energy as explained in E=m c2. Once calculated it was found that energy was 4.3 x 10-3 J in quantity. When Trillions of Hydrogen atoms fuse in such a mechanism, incredibly huge amounts of energy is generated. That’s how the sun generates its power and provides us with energy.
References :
- https://www.universetoday.com/75803/how-does-the-sun-produce-energy/
- https://www.need.org/files/curriculum/guides/energyfromthesunstudentguide.pdf
