We all know that the earth is a rocky planet, and the place where humans live is only the surface of the earth. So is the rocky planet Earth composed entirely of solid state? Perhaps in the eyes of the ancients, the earth is a solid world except for the hard surface, which is the ocean.
However, when human beings entered the age of science and technology, as the understanding of the earth continued to deepen, scientists discovered that although the earth is called a rocky planet, it is not a solid planet, but a planet composed of liquid and solid, in which liquid matter Also accounted for the majority.
Now we all know that the earth has three structures, namely the crust, the mantle and the core. The crust is the outermost structure, with an average thickness of about 17 kilometers, which is also the thinnest layer of the three structures.
The mantle under the crust is a world made of magma. The flowing magma supports the surface. The magma erupted by the volcano comes from the mantle layer, and its average thickness reaches 2,865 kilometers.
The center of the earth is the core, the most mysterious area inside the earth, with a radius of 3470 kilometers. According to current research, the earth’s core is also divided into inner and outer layers. The outer layer is a high-temperature and high-pressure area composed of liquid substances, while the inner core is a solid, high-density sphere composed of iron and nickel.
The temperature of the earth’s interior is constantly increasing as the depth continues to increase. The temperature at the core of the earth has reached about 6000 degrees Celsius, which is almost the same as the temperature on the surface of the sun. So some people have this question: Why is the inside of the earth as hot as the sun? Where does its energy come from? Can one day cool down completely?
In fact, the core temperature of the earth has existed since it was born 4.5 billion years ago. The movement of plates on the surface of our earth, earthquakes, volcanic activity, and geomagnetic changes are all related to the movement of the earth’s core. It is precisely because the interior of the earth is a liquid world that there will be various ecological changes on the surface and the current ecological environment.
If the core of the earth cools down completely, then the earth will become a dead planet without life, just like the current moon, Mercury and Mars. So how does the original energy of the earth come from? The core of the earth needs a strong energy supply to keep moving. What is the origin of this energy?
The original source of energy for the Earth’s core is actually not complicated, it is all related to the 4.5 billion-year-old early solar system. According to modern scientific research, the solar system was born in a solar nebula, and this solar nebula is not an ordinary solar nebula.
We all know that since the universe was born, only hydrogen, helium and a small amount of lithium have appeared, and other elements have not appeared. It was not until the birth of stars that they had the opportunity to transform hydrogen into other elements, but the ability of stars to transform hydrogen was also limited, at most it could only be transformed to the level of element 26, iron.
If the elements after the 26th want to be produced, then stronger energy bursts are needed, and they are also related to stars. When the massive star comes to its end, a supernova will explode, producing a certain amount of various heavy elements. In addition, the collision and fusion of neutron stars will also produce some heavy elements.
It can be seen that the origin of various heavy metal elements is not so easy, they are rare elements in the universe. However, we have also seen that both the earth and other planets in the solar system have rich reserves of metal elements. This shows that the early solar system contained a wealth of various elements and basically covered the entire periodic table.
So how did these elements come from? In fact, it is related to the predecessor of the solar system. Before the solar system, there were two generations of massive stars in the position of the solar nebula. When they reached the end, a supernova explosion produced a large amount of metal elements. Later, the two neutron stars collided and merged. Produce a lot of heavy metal elements.
In this way, these elements formed various chemical molecules in the gas cloud, and under the action of gravity, they continuously gathered to form the sun, eight planets and a large number of other small celestial bodies. The aggregation of material elements forms the primitive celestial embryo, and when the planet is formed, a large number of object clumps will collide and gather at a very high speed. This process will release a large amount of gravitational potential energy and convert it into heat.
Therefore, when the earth was just formed, it was completely a world of lava. Not only was the core of the earth in a molten state, but the surface was also covered with high-temperature magma. This is the original heat source of the earth’s core. They are the release of gravitational potential energy. After the solar system is stabilized, the eight major planets also have their own stable orbits.
At this time, the earth gradually began to cool, and the surface of the earth continued to solidify to form the crust, while the mantle and core sealed under the surface continued to maintain the state of liquid matter. Since liquid matter can flow, it will affect the surface during the flow. The ecological climate is only part of the world, so the earth has a good ecological environment, which provides the conditions for the birth of life.
Will the core of the earth continue to cool? The answer is naturally yes. Since the day the earth stabilizes, its heat has been continuously released, and the earth has continued to cool from the outside to the inside, until the earth’s core has completely turned into a solid state, becoming a dead planet.
Of course, the time taken for this cooling is extremely long. You must know that the earth’s core is not completely releasing heat. It also spontaneously produces a part of energy inside. The main source is the heat generated by the deep decay of heavy element elements in the core.
We know that under the action of gravity, heavy elements will sink and hydrogen elements will rise. Therefore, there are a lot of heavy elements inside the earth. In theory, any element heavier than lead will decay in a limited time until it becomes lead. . For 4.5 billion years, the earth’s core has been undergoing elemental decay, and this slow nuclear reaction has been providing energy to the earth’s core.
Of course, the energy produced by the decay of heavy elements is much smaller than the energy it releases every year. Therefore, from the general trend, there has been a net outflow of heat from the earth’s interior and has been cooling. Of course, it would take at least tens of billions of years for the earth to completely cool down and become a dead planet under normal circumstances.
So can the earth wait until that time? In fact, it is very difficult because the sun will not give us that long. According to the current research, the sun’s life span is only 5 billion years. When the sun’s life comes to an end, it will rapidly expand into a red giant star. At that time, the earth will It will be swallowed and disappear completely, and if the result is good, it may leave a core of iron and nickel.
Therefore, we don’t have to worry about the earth’s cooling and let us lose our homes. Perhaps in billions of years, humans have already become interstellar civilizations. At that time, the entire solar system was home to humans. The earth or the solar system could not survive. We can go to other young people. The galaxy survives and continues to maintain the prosperity of human civilization.