Where did the earth come from?

At present, the most authoritative statement is that at the beginning of the formation of the solar system, more than 99% of the matter gathered in the center to become the sun, and some scattered material fragments revolved around the sun. After a long time of collision and gravity, the scattered debris gradually aggregated into nine planets, but the earth at that time was just a chaotic mass. After hundreds of thousands of years, matter gradually cooled and solidified, forming the original shape of the earth. Hundreds of thousands of years later, due to the gravity of the earth, the gas produced by the chemical reaction inside the earth is ejected and stored around the earth, forming an atmosphere and combining with hydrogen and oxygen to form water. Then through the energy radiation of the sun, the electric and magnetic fields of the earth itself and the suitable living environment, organic matter is produced from the water, which is the ancestor of all life. ...

The earth is a member of the solar system. The solar system family consists of the sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto and 500,000 asteroids, satellites and comets. The sun is the mother of the solar system. Before the formation of the solar system, it was a nebula composed of hot gas. When the gas cools and contracts, it makes the nebula rotate. Due to the action of gravity, the gas and wind grass contract, the rotation speed is accelerated, and the nebula becomes a flat disk. As we know, the washing machines used to wash clothes in modern families all have dehydrators. When wet clothes are put in, the dehydrator rotates quickly, and the water in the clothes will be "thrown out", and the wet clothes will become dry clothes. The force that throws water out is the force that leaves the center when the water drops move in a circular motion, which is called centrifugal force. Similarly, when the rotating nebula rotates while contracting, the centrifugal force of the surrounding matter exceeds the gravity of the center, and a ring is separated. In this way, one ring after another came into being. Finally, the central part becomes the sun, and the surrounding rings become planets, one of which is the earth, which was produced four or five billion years ago.

This is a scientific hypothesis, which was put forward by the German philosopher Kant and the French mathematician Laplace in the18th century. People call it Kant-Laplace nebula theory. 1944, the German physicist Weizak developed this theory.

The research on the origin of the solar system and the formation of the earth continues and is constantly improving. However, the earth is our mother, nurturing our growth. We humans should know it and understand it. Even if one day, humans move to other planets, we will always miss it.

The earth is a member of the solar system. The solar system family consists of the sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto and 500,000 asteroids, satellites and comets. The sun is the mother of the solar system. Before the formation of the solar system, it was a nebula composed of hot gas. When the gas cools and contracts, it makes the nebula rotate. Due to the action of gravity, the gas and wind grass contract, the rotation speed is accelerated, and the nebula becomes a flat disk. As we know, the washing machines used to wash clothes in modern families all have dehydrators. When wet clothes are put in, the dehydrator rotates quickly, and the water in the clothes will be "thrown out", and the wet clothes will become dry clothes. The force that throws water out is the force that leaves the center when the water drops move in a circular motion, which is called centrifugal force. Similarly, when the rotating nebula rotates while contracting, the centrifugal force of the surrounding matter exceeds the gravity of the center, and a ring is separated. In this way, one ring after another came into being. Finally, the central part becomes the sun, and the surrounding rings become planets, one of which is the earth, which was produced four or five billion years ago.

This is a scientific hypothesis, which was put forward by the German philosopher Kant and the French mathematician Laplace in the18th century. People call it Kant-Laplace nebula theory. 1944, the German physicist Weizak developed this theory.

The research on the origin of the solar system and the formation of the earth continues and is constantly improving. However, the earth is our mother, nurturing our growth. We humans should know it and understand it. Even if one day, humans move to other planets, we will always miss it.

BIGBANG

Several hypotheses about the origin of the earth

The earth is the cradle of mankind. For thousands of years, human beings have never stopped exploring the planet where they live. But it was not until18th century that Copernicus put forward the scientific hypothesis of the origin of the earth after Heliocentrism and Newton discovered gravity and the invention of the telescope. The main assumptions of representativeness are as follows:

(1) 1755 German philosopher 1? Kant put forward the nebula theory of the origin of the sun in his book General History of Nature and Theory of Celestial Bodies. Kant believes that the universe and space are dispersed by granular and dispersed primitive matter. Due to gravity, larger particles attract smaller particles and gather to form large and small lumps. After the lump is formed, the gravity also increases, and the aggregation accelerates, and the fruit forms a huge sphere in the center of the diffused lump. Due to the repulsive force and the impact force during polymerization, this huge sphere became a rotating body, forming the original sun. Under the action of the primitive sun, the primitive materials other than the sphere form a flat rotating nebula around the equatorial sun, and the nebula materials gradually gather into lumps of different sizes and gradually form planets. Planets revolve around the sun and rotate under the combined action of gravity and repulsion. Its model is: elementary particle-lump-planet.

(2) Laplace said 〓 1796 is a French mathematician PS? Laplace independently put forward the nebula theory about the origin of the solar system in his Theory of Cosmic Systems. Laplace believes that the original material of the solar system is a hot spherical nebula, which is much larger in diameter than the current solar system and rotates very slowly. Due to heat dissipation and cooling, the nebula gradually shrinks and becomes dense, and the rotation speed gradually becomes faster. Due to the increasing centrifugal force near the equator, the nebula gradually becomes a nebula disk. When the centrifugal force exceeds the centripetal force, the matter at the equatorial edge separates to form a rotating ring (Laplace ring), and other rings equal to the number of planets are separated one after another. The central part of the nebula eventually formed the sun, and during the rotation of each ring burning the sun, the substances in the ring gradually gathered into some clots to form planets. Similarly, planets separate rings and condense into satellites. This genetic model can be summarized as: hot gas cloud-separation ring-lump-planet.

(3) 〓 Huo Yier-Shazman hypothesis In the 1960s, the British astronomer E? Huo Yier and German astronomer E. Shazman put forward a new hypothesis based on the mechanism of electromagnetic action. They believe that the primitive solar system is a condensed nebula with low temperature and slow rotation. As the contraction intensifies, the rotation speed increases. When it shrinks to a certain extent, the poles gradually flatten, the equator protrudes and throws out matter, gradually forming a disk. After that, the centrosome continued to contract, eventually forming the sun. Because there is a strong magnetic field in interstellar space, the thermonuclear reaction of the sun emits magnetic radiation, which makes the surrounding gas disk become plasma in the magnetic field. When the sun is separated from the disk, the magnetohydrodynamic interaction between them produces a magnetic moment, which transfers the angular momentum of the sun to the disk and makes the disk expand outward. Due to the solar wind, light matter gathers away from the sun to form a wood-like planet, while heavy matter gathers near the sun to form a earth-like planet.

(4) China astronomer Dai Wensai put forward the theory of "nebula" in 123078+0974, which made China's research on the origin of the solar system enter the advanced ranks in the world. Dai Wensai believes that 5.7 billion years ago, there was an interstellar cloud several thousand times larger than the solar system, which caused eddy currents inside the contraction and split into thousands of nebula clusters, one of which formed the original nebula of the solar system. Because the nebula is formed in a vortex, it is rotating at first, with great angular momentum, and contracts due to self-gravity. In the process of contraction, due to the conservation of angular momentum, the rotation speed is accelerated, the nebula is gradually flattened, a lot of energy is released, and the temperature is gradually increased. When the original nebula shrinks to the size of Neptune's orbit today, the centrifugal force at the equator is equal to the gravitational force, and the matter at the equator no longer shrinks, but the contraction inside the nebula continues, thus forming a double concave mirror-shaped nebula disk with thick edges and thin center. The central part of the disk has a high shrinkage density to form the sun, and the solid particles of other substances gradually gather into planets through mutual collision and gravitational accretion.

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The earth is a planet in the solar system. Its exterior is surrounded by gas. When the earth was first formed, it was a huge fireball. With the gradual decrease of temperature, heavier substances sink into the center and form the core. Lighter substances float to the ground and form the crust after cooling. About 4.5 billion years ago, the earth was about the same size as it is today. There was neither an atmosphere nor an ocean on the primitive earth. In the first few hundred million years, due to the thin crust of the primitive earth and the constant impact of small celestial bodies, the molten liquid inside the earth kept surging, and earthquakes and volcanic eruptions could be seen everywhere. During the volcanic eruption, a cloud-like atmosphere rises from the inside. These clouds are filled with water vapor and then fall back to the ground through rainfall. Rainfall filled depressions and valleys, and finally water gathered to form a primitive ocean. In Proterozoic, 2.5 billion to 500 million years ago, a large area of connected land appeared on the earth, and the earth was formed.

The German philosopher Kant put forward the theory of "nebula" in 1755. According to the astronomical observation data at that time, he thought that there were primitive scattered particles of matter in the universe, which rotated around the center and gradually concentrated on a plane. Finally, the central matter forms the sun, and the matter on the equatorial plane forms planets such as the earth and other small celestial bodies. This "nebula theory" gradually formed a school of the origin theory of the solar system.

The formation of the earth, according to the nebula theory, the protostar of the earth is about 500 times heavier and 2000 times in diameter than it is now. Due to the differences between heavy countries, heavy elements sink into matter, forming a thick and heavy core surrounded by light matter. When the sun shrinks inside and reacts, it heats up, glows and radiates a lot of particles. When these particles sweep across the earth's surface, they "drive away" the light matter on the earth's surface. So there are only those dense and basically solid substances left on the earth.

There are some assumptions and some truth. If someone thinks that the earth has been thrown out of the sun; Some people think that a binary star of the sun became the earth after breaking into pieces. These assumptions are not accepted by everyone as Xingyun said.

BIGBANG released a lot of matter and huge energy, and I don't know how many years have passed. The universe has not been finalized, there are no galaxies and planets, and there is no life. There is darkness everywhere, and hydrogen atoms are still in the void; The dense air mass scattered everywhere gradually becomes larger in indecision, and hydrogen gathers into an air mass much larger than that of modern stars; Finally, the torch of nuclear reaction is lit in these atmospheric masses. In this way, the first generation of stars came into being, thus illuminating the dark space. Nuclear fission produces heavy elements and dust left by hydrogen combustion, which are the raw materials needed by future planets and life forms.

Superstars soon exhausted their nuclear fuel reserves. Affected by the big bang that happened later, these stars sent most of the matter back to the thin gas that originally formed them. Then, in the dense clouds between stars, a new polymer composed of various elements was formed, thus producing a new generation of stars. Although the smaller aggregates nearby can also become larger, they are too small to stimulate nuclear fission, so they are developing towards planets. One of them is a small star made of rocks, which is the early earth.

In the process of continuous melting and condensation, the early earth released a lot of methane, ammonia, water and hydrogen, which were captured by the earth and formed the primitive atmosphere and ocean. Under the bath of the sun, the earth becomes warmer and warmer, and storms, lightning and thunder are produced. Volcano erupts and magma surges. All these processes make the molecules in the primitive atmosphere split, the fragments of molecules recombine, and gradually generate increasingly complex material forms, which are dissolved in the primitive ocean. After a while, the sea water turned into a warm and thin liquid. On the surface of the earth, the combination of molecules and complex chemical reactions have taken place. One day, it happens that one molecule can take other molecules as raw materials and copy the same molecule as itself. With the passage of time, molecules have emerged that can replicate themselves more accurately and finely. Natural selection favors those molecules with the strongest replication ability. Which molecules replicate well will increase. Due to the consumption of molecular replication and the complex condensation of self-replicating organic molecules, the original seawater gradually becomes thinner. Unconsciously, life slowly appeared.

BIGBANG released a lot of matter and huge energy, and I don't know how many years have passed. The universe has not been finalized, there are no galaxies and planets, and there is no life. There is darkness everywhere, and hydrogen atoms are still in the void; The dense air mass scattered everywhere gradually becomes larger in indecision, and hydrogen gathers into an air mass much larger than that of modern stars; Finally, the torch of nuclear reaction is lit in these atmospheric masses. In this way, the first generation of stars came into being, thus illuminating the dark space. Nuclear fission produces heavy elements and dust left by hydrogen combustion, which are the raw materials needed by future planets and life forms.

Superstars soon exhausted their nuclear fuel reserves. Affected by the big bang that happened later, these stars sent most of the matter back to the thin gas that originally formed them. Then, in the dense clouds between stars, a new polymer composed of various elements was formed, thus producing a new generation of stars. Although the smaller aggregates nearby can also become larger, they are too small to stimulate nuclear fission, so they are developing towards planets. One of them is a small star made of rocks, which is the early earth.

In the process of continuous melting and condensation, the early earth released a lot of methane, ammonia, water and hydrogen, which were captured by the earth and formed the primitive atmosphere and ocean. Under the bath of the sun, the earth becomes warmer and warmer, and storms, lightning and thunder are produced. Volcano erupts and magma surges. All these processes make the molecules in the primitive atmosphere split, the fragments of molecules recombine, and gradually generate increasingly complex material forms, which are dissolved in the primitive ocean. After a while, the sea water turned into a warm and thin liquid. On the surface of the earth, the combination of molecules and complex chemical reactions have taken place. One day, it happens that one molecule can take other molecules as raw materials and copy the same molecule as itself. With the passage of time, molecules have emerged that can replicate themselves more accurately and finely. Natural selection favors those molecules with the strongest replication ability. Which molecules replicate well will increase. Due to the consumption of molecular replication and the complex condensation of self-replicating organic molecules, the original seawater gradually becomes thinner. Unconsciously, life slowly appeared.

Respondent: 343086998- Scholar Level 3 4-30 14:50

The formation of the primitive earth

Before the formation of the earth, many asteroids in the universe revolved around the sun, and these planets collided with each other to form the original earth. At that time, the earth was still a fiery fireball. With the gradual reduction of collisions, the earth began to cool slowly from the outside to the inside, resulting in a thin crust-the crust. At this time, the interior of the earth is still in a state of high temperature. A large number of gases are ejected from the earth's interior,

There is a lot of water vapor in it, forming the atmosphere around the earth. The earth is not too close to the sun to evaporate water vapor, and the earth itself has enough gravity to pull the atmosphere, so the earth will have a unique atmospheric environment.

After the formation of the atmosphere, it began to rain, forming a primitive ocean.

About 4.7 billion years ago, dust gathered in the universe, forming the earth and other planets in the solar system. At that time, the air did not contain oxygen, but it contained a lot of carbon dioxide (carbonic acid gas) and nitrogen.

The original earth is very small, but it is constantly hit by dust and small stars in the universe, and its volume is constantly increasing. Moreover, the energy and temperature accumulated during the impact process continue to rise and finally melt into liquid.

Soon, the number of star collisions decreased, and the temperature of the earth's surface decreased, forming the crust. This is the surface of the earth today. However, the magma inside the earth keeps spewing, forming a large number of volcanoes. The water vapor in volcanic ash cools and condenses into water, thus forming the ocean.

The formation of the primitive earth

Before the formation of the earth, many asteroids in the universe revolved around the sun, and these planets collided with each other to form the original earth. At that time, the earth was still a fiery fireball. With the gradual reduction of collisions, the earth began to cool slowly from the outside to the inside, resulting in a thin crust-the crust. At this time, the interior of the earth is still in a state of high temperature. A large number of gases are ejected from the earth's interior,

There is a lot of water vapor in it, forming the atmosphere around the earth. The earth is not too close to the sun to evaporate water vapor, and the earth itself has enough gravity to pull the atmosphere, so the earth will have a unique atmospheric environment.

After the formation of the atmosphere, it began to rain, forming a primitive ocean.

About 4.7 billion years ago, dust gathered in the universe, forming the earth and other planets in the solar system. At that time, the air did not contain oxygen, but it contained a lot of carbon dioxide (carbonic acid gas) and nitrogen.

The original earth is very small, but it is constantly hit by dust and small stars in the universe, and its volume is constantly increasing. Moreover, the energy and temperature accumulated during the impact process continue to rise and finally melt into liquid.

Soon, the number of star collisions decreased, and the temperature of the earth's surface decreased, forming the crust. This is the surface of the earth today. However, the magma inside the earth keeps spewing, forming a large number of volcanoes. The water vapor in volcanic ash cools and condenses into water, thus forming the ocean.

When we have a relatively complete and clear model of the solar system, it is possible for us to further explore the formation of the earth. On the basis of the knowledge we have mastered, we will naturally no longer think that the formation of the earth is completely isolated and spontaneous, because the sun, as a member of the solar system family, is quite clear. However, we have reason to question the origin of the earth and other stars in the solar system 4.6 billion years ago.

French natural scientist George Louis Buffon did not answer this question according to the story of the Bible (of course, the Bible has no scientific basis). Natural scientists have always believed that the earth has existed for 75 thousand years. 1749, Buffon explained that there is a "kinship" relationship between the planets including the earth and the huge sun, just like the relationship between chickens and hens. Perhaps, he once thought that the earth was born from the sun.

Buffon once thought that the sun collided with other giant celestial bodies, and the scattered debris cooled down during the collision, forming the earth. This hypothesis is interesting, but it doesn't explain why other planets and the sun formed. Maybe the sun existed in the beginning.

We need a more reasonable explanation. After Kepler described the grand plan of the solar system, the general situation of this system became very clear. All the planets run almost on the same plane (this complete model of the solar system is similar to a giant pizza box) and rotate in one direction around the sun, just like the moon revolves around the earth or Saturn's satellites revolve around Saturn. In addition, these planets also rotate around their own axes, and so does the sun. Inspired by this, astronomers believe that if the solar system did not come from the same celestial body, it would be impossible to show so many similarities.

Before studying the origin of the earth, we should first discuss how the sun was formed. The conclusion of this study is not only applicable to other planets, but also of reference value to the formation of other starry sky in the universe. 16 1 1 is an early telescope test period. In the course of observation, German astronomer Saizhi Marius discovered a glittering and hazy celestial body in Andromeda, which we call the Andromeda nebula (which means "cloud" in Latin). 1694, Hercules (inventor of the pendulum) discovered a similar nebula when observing Orion, which is the Orion nebula. Since then, other nebulae have been discovered.

Some people speculate that these luminous nebulae are a combination of dust and gas, and these components have not yet aggregated into real stars. 1755, the German philosopher Emmanuel Kong Di imagined in his works that all the stars are prototypes of these nebulae, and he thought that nebulae could slowly gather together and start to rotate by their own strength. When nebulae gather, stars are formed in the central part and planets are formed in the peripheral part. This hypothesis basically explains that planets run on the same plane, and the directions of revolution and rotation are the same.

1798, French astronomer Paris serge de laplace probably didn't know what Carter had done before. He described the same idea in a book, but his content was more detailed. He believes that the nebula is slowly shrinking, and in the process of shrinking, the rotation speed of the nebula is rapidly accelerated. In fact, this idea was not initiated by Laplace. Shrinkage is only the result of gravity, which is a common phenomenon in the solar system, that is, doing work. Every skater has tried this. When you spin on the ice, the tighter your arms are, the faster you spin. The nebula is contracting, rotating faster and faster, and its center protrudes outward, leaving its original position. This process is not imaginary, but the result of centrifugal force, which can be seen everywhere on the earth. Laplace imagined that the "falling off" parts gathered together and eventually formed a planet. At this time, the nebula slightly in the center is still gathering, thus giving birth to another planet. If this situation continues, planets will gradually form and they will turn in the same direction. Finally, the sun forms in the rest of the central region. Because Carter and Laplace explained the formation process of the solar system on the basis of the nebula contraction theory, they called this hypothesis "nebula hypothesis" (this theory has not been fully proved).

For a century, astronomers have been satisfied with the theory of "nebula hypothesis". Unfortunately, the defects of this theory have also been exposed one after another. The reason comes from the concept of "angular momentum". Angular momentum is a physical quantity to measure the rotational ability of an object, which includes both rotation around the rotation axis and rotation around the rotation axis. When Jupiter revolves around its own axis, it also revolves around the sun. Its angular momentum is 30 times that of the giant sun, and the sum of angular momentum of all planets is 50 times that of the sun. If the solar system was only a single nebula with angular momentum in the early days, how could it concentrate so much angular momentum on such a small mass and release it to form these planets? Astronomers failed to find the answer in the "nebula hypothesis" and began to seek other theories. 1900, American scientists Thomas Zhuoud Chamberlain and forest Ray Morton picked up Buffon's theory again in their research. They believe that a long time ago, when another star passed near the sun, under the action of gravity, some of them separated from the mother body and formed new individuals. These new individuals rotate rapidly under the action of gravity, thus gaining a lot of angular momentum. After separation, these individuals gradually cooled down, and their volume also decreased, becoming solid or microsatellite, and further colliding to form planets. The hypothesis that the matter of two stars gathers together to form a planetary family is called "MSI theory".

There are important differences between the above two viewpoints. If the "nebula theory" is correct, then every star can form a planet; If the "microsatellite theory" is correct, planets can only be formed after the collision of stars, and the distance between stars is very long and the movement is quite slow. Compared with their distance, the collision between them is extremely rare. So the difference between the two viewpoints is that the "nebula theory" thinks that many galaxies can be formed, while the "microsatellite theory" thinks that galaxies can only be formed in a few stars.

Facts show that the "MSI theory" is also unreasonable. 1920, the British astronomer arthur stanley eddington pointed out that the temperature inside the sun is much higher than people thought, and the substances separated from the sun (or falling from other stars) are so hot that they spread into space before cooling down to form planets. American astronomer Lyman Spitzer gave a convincing demonstration in 1939.

1944, German scientist Karl frantic von Weitzsack regained the "nebula hypothesis" and further developed and perfected this theory. He believes that the rotating nebula gradually shrinks to form planets, first the first one, and then other stars in turn. Astronomers can consider the electromagnetic effect in the nebula (electromagnetic phenomena had not been discovered in Laplace's time) to explain how angular momentum was transferred from the sun to the planet.

By the way, what is the state of heat inside the earth during the formation from micro-satellites to planets? Microsatellites move very fast, and they contain huge kinetic energy. During the collision, the motion stops temporarily, so some kinetic energy becomes heat energy, and then they start to run to form planets. The heat energy converted from kinetic energy is quite large, which is also the reason why the geocentric temperature reaches 5000℃. Obviously, the bigger the star, the higher the degree of energy conversion, and the higher the core temperature after the formation of the planet; Similarly, the smaller the star, the less kinetic energy it contains, and the lower the temperature of the core when it forms a planet. To be sure, the temperature in the center of the moon is lower than 5000℃ because it is much smaller than the earth. On the other hand, Jupiter is much bigger than the earth. It is the largest of these planets, and its core temperature must be higher. Some predictions show that Jupiter's core temperature can reach 50,000℃. So far, the theory of "Nebula Hypothesis" is satisfactory.