The Sun consists of three parts: the interior, the outer layer, and the solar atmosphere. The outer layer of the Sun is similar to the boundary that exists between the Earth and its atmosphere. The core is denser than the outer layer. It is possible to observe the outer layer of the Sun, but it is not possible to observe the interior. Therefore, any knowledge about the interior of the Sun is dependent on interpretation of data collected about the events that occur on the outer layer. The interior consists of three parts: the core, the radiation zone, and the convection zone. The Sun is made up of matter that is not in a solid, liquid, or gaseous state; rather it is in the plasma state of matter. In the plasma state, due to the very high temperatures, the electrons move away from the nucleus. The elements in this plasma state are charged particles (electrons and protons), which are inclined to react with magnetic and electrical fields. The ionized gas, in the state of plasma, magnetizes the magnetic field of the Sun, increasing its potential by twisting it and forming magnetic field lines. In certain zones in which the magnetic field is strong, the magnetic fields, which are similar in shape to a loop, independently break off and are scattered throughout the solar atmosphere.
More than 99% of the matter in the universe is in a state of plasma. The energy that the Sun distributes comes from the core, which is like a blast furnace; here matter is pure energy or is converted to energy. In the core hydrogen atoms are combined and helium is created through nuclear fusion, which occurs at very high temperatures. During nuclear fusion, enormous amounts of energy are emitted. The total capacity of the Sun’s outer layer that emits energy is around 3.86 x 1,026 watts. However, only 1,368 watt per m2 comes into the orbit of the Earth. This energy results in the light that we see when we look at the Sun. The core of the Sun is 160 times denser than water on Earth. The temperature in the core is about 15 million °C. If the Sun had not been created at this density and high temperature, such a great amount of energy could not be produced. The energy produced in the core is conveyed to the radiation zone, so called as energy here is conveyed by radiation. The energy produced in the core heats everything while moving to upwards and when it comes close to the outer layer, it loses heat and energy. For instance, there is 1-2 million °C of heat that is dissipated before the end of the radiation zone. At the point where the radiation zone ends, the density of the matter is equal to the density of water on Earth. The energy is conveyed by radiation in the interior part of the Sun, while being conveyed by convection in the outer layer. The source of energy that maintains the light and heat of the Sun is the furnaces at the core. The heat decreases in proportion to the distance from the core. Curiously enough, when moving away from the photosphere (radiation zone) towards the corona, one might think that the temperature in the solar atmosphere should decrease, but in fact it increases. The interior of the corona is almost as hot as the core of the Sun, but the temperature decreases in the outer part of the corona. The cooling process that begins when moving away from the core stops at the corona and the temperature rises from 100,000 °C to 1-5 million °C. Scientists have not yet resolved why the corona has this very high temperature.
The outer layer of the Sun is very stormy. We can compare the events in the outer layer to water boiling in a kettle. This layer is known as the convection zone, which is kept in place by the magnetic field in the corona. The gas pressure in this zone is relatively higher than the magnetic field pressure. Therefore the magnetic field retreats inward and is twisted as a result of the turbulent movements of gas. These movements fulfill the role of enlarging the magnetic field lines of the corona. In the corona, the magnetic field pressure is higher than the gas pressure. It is possible that the extra energy conveyed to the magnetic field is transferred to the plasma in the corona. The energy, in the state of hydromagnetic waves, is squeezed and converted into energy. But we do not know exactly how the energy in the magnetic field is converted to heat in the corona.
The most interesting research topics at the moment are the transfer of energy to the corona and the storage mechanisms for this energy. Matter is heated in the convection zone and expands and rises to the surface. It cools as it rises to the outer layer, becoming denser and then, in a plasma state, sinks down again. This cyclic movement, consisting of a rise and fall, is what is meant by the term “convection.” This movement is conducive to the conveyance of energy from the base of the convection zone to the top. The matter approaching the top cools down and becomes denser here, distributing its energy to the environment. The rising and falling movements of matter in this convection zone are similar to the circular movement observed in water boiling in a kettle. These movements cause the formation of strong magnetic fields in the outer layer of the Sun.
The extremely hot gas in the corona moves away from the Sun. When this hot gas mass heads to the planets it is known as “solar wind.” Solar winds are the officers in charge of changes in the climates of planets. This activity in the solar atmosphere causes atmospheric air currents that bring about snow and rain. There are relatively few magnetic fields in the outer layer of the Sun, while there are a number of magnetic fields in the solar atmosphere. The interplanetary magnetic field is formed as a result of the Sun’s magnetic field. Coronal mass ejections expand away from the Sun at speeds that measure as much as 1,250 miles per second. These blasts carry up to ten billion tons of plasma away from the Sun. It may take a few days for the matter, which covers distance at a speed of 60-600 miles per second, to reach the Earth. Solar flares move at the speed of light and can reach the Earth in eight minutes. If coronal mass ejections reach the atmosphere of the Earth, they can create geomagnetic storms. Auroras (radiation that can be observed in Polar zones) are the atmospheric events related to the coronal mass ejections. Large geomagnetic storms can cause electrical power outages and damage communication satellites.
Astronomers record the xrays that emanate from the Sun in the same way that a doctor records the occurrences of pain in patients. It has been discovered that there is a strong correlation between the density of solar flares and the pains of those who suffer migraines. Even if this correlation is statistically meaningful, more controlled research needs to be carried out to understand if there is any biological significance. The storage of magnetic energy in the solar atmosphere and the ejection of the same, like a sudden explosion, cause solar flares. A solar flare occurs when magnetic energy that has built up in the solar atmosphere is suddenly released. During such an explosion, radiation is emitted across virtually the entire electromagnetic spectrum. The amount of energy released is the equivalent of millions of 100-megaton hydrogen bombs exploding at the same time. Considering how just one hydrogen bomb is enough to destroy the entire world, we must thank the All-Powerful God Who placed the Sun at an ideal distance, protecting us both from freezing and burning. The energy released during a flare is typically to the order of 1027 ergs per second. This energy is ten million times greater than the energy released by a volcanic explosion.
The system in which magnetic fields are produced in the Sun can be the cause of some changes on Earth. For example, between the years of 1600 and 1850s solar activities decreased and low temperatures (a minor ice age) were recorded on Earth, especially in much of Europe and North America. Therefore, solar activity carries out its duty on the order of God and works for the adjustment of climates on Earth. It was determined that the temperature differences measured at 6 miles above the North Pole (in the boundary of troposphere/stratosphere) were related to a eleven-year cycle of sunspot explosions. The stratosphere heat over the Polar zones is relatively less cold when the Sun is active, depending on the stratospheric winds. However, the physical mechanisms have not yet been determined.
How do the planets stay in orbit around the Sun?
There are two hypotheses on this matter: one of them says that the revolving of the planets around the Sun while they are in their or bit is dependent on the movement around the common mass instead of on the force of gravity. The other theory is that the magnetic field forces, which are created as cycles in the core of the Sun, play an important role in interplanetary gravity. The difference between the hypotheses stems from the structure of the orbits in terms of causes. Circular orbit is formed by the force of gravity, while elliptic orbits are the result of common mass movement. Therefore, it would be more sensible to say that while explaining the phenomenon of planets staying in their orbit around the Sun that a role is played by both common mass movement and matter cycles in the core, reminiscent of the oscillations in the core of the Sun, and the magnetic field that is produced. There are a number of verses in the Qur’an about the Sun and the sky. One of these is: “And the Sun runs the course appointed for it for a term to its resting-place for the stability of it(s system)” (Yasin 36:38). Bediüzzaman Said Nursi says, The Sun is a light-diffusing tree, and the planets are its moving fruits. But unlike trees, the Sun is shaken so that the fruits do not fall. If it were not shaken, they would fall and be scattered.1
The period of the actual rotation of the Sun is approximately 27 days. The active zones of the sunspots can be observed on the side of the Sun that faces the Earth. The Sun’s movement forms an interesting orbit. Although it is not solid (being in a gas and plasma state), the outer layer of the Sun has different speeds of rotation at different latitudes. Scientists have lately started to use acoustic detectors to receive the signals that emanate from the Sun. The acoustic detectors are used to understand the rising and falling wave movements that this noise causes on the surface of the Sun. Scientists are trying to understand how the sound waves behave in an environment made up of other material, such as oil and vinegar, which form a layer in the water, and they then try to decipher the inner structure of the Sun by making analogies with the events that occur within the Sun. The sound waves that are related to events that occur at the center of the Sun vibrate like a spring. Measurements are made by special acoustic detectors and these reflect the cycles within the Sun. The sound that emanates from the interior parts of the Sun is converted into magnetic waves. These magnetic waves always move, in the form of oscillations that first rise above (to the solar atmosphere) then fall down (to the core of the Sun). The movements within the center of the Sun display rhythmic motions, like water in a pool that has been disturbed. Measuring the smallest sound waves that come from the very core of the Sun, Steven Tomczyk (1994) found that the core of the Sun rotates in a way that is similar to the rotation of the Earth. To put it another way, he found out that the rotation at the core of the Sun occurred independently of latitude and depth, unlike movement in the outer layer of the Sun. While explaining the meaning of the word “li mustaqar” (resting-place) in the Qur’an, Nursi refers to this rotation as follows:
Since the All-Wise Maker operates behind the veil of apparent causality, He has tied the planets to the Sun by His law of gravity and causes them to revolve with distinct but regular motions according to His universal wisdom. To produce gravity, He has made the Sun’s movement on its axis an apparent cause. Thus a resting place means that “the Sun moves in the place determined for it for the order and stability of its own (solar) system.” Like the Divine law, that motion produces heat, heat produces force, and force produces gravity.2
Some astronomers compare the Sun to a bell that is periodically struck. They also state that the cycles that occur within the Sun and at the outer layer of the Sun play a role in the formation of magnetic fields, gravity forces, and the common mass center of the Sun. As a result of the interconnectivity of all these factors, how the planets revolve around the Sun while staying firmly in their orbits (without being scattered in terms of causes) can be explained. The existence of this huge star and its continuity in a controlled way is a serious matter, which, even though we often take this miracle for granted, must be contemplated. The fact that the Sun is so vital for us, yet that we have no control over it shows us that this fire ball is in the service of humanity thanks to the order of the Divine Will.
- Nursi, The Words, The Light, Inc., NJ: 2005, p. 413. 2. Ibid.