The Energy Source of the Sun
There is a rationale behind the earth being the only planet in the solar system in which life exists and blossoms. Scientists have attributable this occurrence to the fact that the earth is the only place that is known to have all the suitable conditions for the existence of life. The major factor for such reasoning is that the earth is located within the most excellent habitable zone from the sun, which signifies that it is in the best spot (not very far or close) to get the sun’s ample energy that encompasses heat and light necessary for chemical reactions. What may appear baffling is what exactly the energy source of the sun is (Borexino Collaboration 384). This paper explains the steps entailed in the generation of the sun’s energy and the manner in which it reaches the earth. The sun gets its energy from a process of the massive fusion reaction.
Scientists are convinced that the process of fusion reaction started the moment a massive cloud of particles and gas (that is, nebula) disintegrated because of the force of its gravity, also referred to as the Nebula Theory. The process did not just create the huge ball of light that is found at the central position of the solar system but also elicited a practice where hydrogen, amassed at the center, started fusing to release solar energy. Commonly referred to as nuclear fusion, the progression generates a surprisingly great quantity of energy in terms of heat and light (Voronchev 477-479). Making the produced energy travel from the central position of the sun to all corners of the universe (encompassing the earth) entails a number of vital steps. Eventually, it is all associated with the layers of the sun with respect to the function undertaken by every one of them in ensuring that the produced energy reaches the earth where it can assist in the creation and sustenance of life.
The sun’s core acts as the section that stretches from the central point to approximately twenty percent of the solar radius. It is at the core where the sun’s energy is created through the conversion of hydrogen atoms into helium molecules (Borexino Collaboration 385). This is enabled by the excessive temperature and pressure that are present in the region. The outcome is the union of four hydrogen molecules into an alpha particle; a couple of neutrons and another of protons are fused into a particle that resembles the helium nucleus. In the course of the progression, two positrons and neutrinos (that convert two protons into neutrons), as well as energy are emitted. The core acts as the only section of the sun where a significant quantity of heat is generated through fusion. It has been established that ninety-nine percent of the energy generated at the core occurs at about 25% of the radius of the sun beyond which fusion does not happen. The other portions of the sun become hot as a result of the transfer of the energy produced at the core across the successive layers before getting to the photosphere and being released into space as sunlight. The energy source from the core is released at an energy conversion pace of 4.3 million metric tons for every second hence yielding approximately 3.85×1026 watts each second.
The radiative zone is found just adjacent to the core and stretches out to approximately 0.7 solar radiuses. Though thermal conversion does not take place in the radiative zone, the solar material therein is dense and very hot to the extent that thermal radiation is the only thing required for the transmission of the intense heat emanating from the core outwards. In essence, it involves ions of helium and hydrogen releasing photons that move a short distance prior to their re-absorption by other ions (Borexino Collaboration 386). The produced energy reduces to some extent as it crosses this layer to the convective zone, from about seven million kelvins at the core to nearly two million kelvins. The convective zone acts as the outer layer of the sun where rising thermal cells transmit most of the heat energy outward to the photosphere.
The photosphere marks the observable surface of the sun where heat and light convected and radiated is released into space. Since the outer surface is considerably cooler when judged against the central part, the sun’s image seems brighter at the middle than on the edges (Borexino Collaboration 385). The thickness of the photosphere is hundreds of kilometers and the energy emitted from it moves through space to reach all planets, including the atmosphere of the earth. The upper surface of the earth’s atmosphere (ozone) sifts most of the ultra-violet radiation from the sun although some pass through.
The sun receives its energy through a progression of the massive fusion reaction. Studies affirm that the process started the time nebula disintegrated due to the force of its gravity. Apart from the practice creating the energy originating from the core, it also educed a progression through which hydrogen, at the center, started fusing to produce solar energy; nuclear fusion.
Borexino Collaboration. “Neutrinos from the primary proton-proton fusion process in the Sun.” Nature, vol. 512, no. 7515, 2014, pp. 383-386.
Voronchev, Thomas. “On nonthermal processes in the core of the Sun.” Physics of Atomic Nuclei, vol. 78, no. 4, 2015, pp. 477-481.