After human beings form civilization, they have infinite interest in the world we live in, and are constantly exploring some unsolvable mysteries. On the road of continuous exploration, some questions have different answers at different times. This is also an inevitable process of human civilization’s quest for knowledge.
We all know that the road to human science began as early as the 19th century. At that time, there were two major problems in the scientific community that have been plagued many scientists. One problem is why the sun glows and heats up, and the other problem is the age of the earth. .
Of course, these two questions can be answered easily for us now, but for the scientific community that was just starting out in the 19th century, it puzzled many scientists. As for the two problems, the scientists at the time did not find a good solution, and put forward many answers that made us laugh now.
For example: Herschel, who discovered Uranus, believes that the sun has a luminous atmosphere, and outside the atmosphere is a habitable environment, where solar people may live; German physicist Meyer believes that the sun’s energy source is similar to burning Coal; Scottish physicist Waterston believes that the sun’s energy comes from the collapse of gravity.
These bizarre answers are very ridiculous to people nowadays, but these answers were all put forward by the great scientists at the time. It is precisely with this spirit of exploration that is not afraid of future generations’ jokes, humanity’s scientific road can go faster and farther.
In the 1920s, British scientist Eddington proposed an answer that was close to the truth. He believed that the energy source of the sun was the fusion of hydrogen. However, it was later discovered that the temperature of the core of the sun could not cause hydrogen fusion. The mystery of the sun’s glow and heat It’s deadlocked again. It was not until later that Gamow discovered the quantum tunneling effect that the problem of hydrogen fusion in the inner core of the sun was really solved.
Later, Hansbet worked out the proton chain reaction, and finally understood the principle of the sun’s luminescence and heat, and also figured out the operating mode of solar energy. Through the solution of these mysteries, we have also successfully calculated the age of the sun and its ultimate lifespan. According to calculations, the age of the sun today is about 4.6 billion years old, with a life span of up to tens of billions of years.
After solving the age of the sun, how can the age of the earth be understood? Compared with the illusion of studying and exploring the age of the sun, there is more exploration of the age of the earth. Although human beings live on the earth, they don’t know much about the earth. Even with the current technology, they know very little about the secrets of the ocean and the inside of the earth.
The exploration and research on the age of the earth is much more than the age of the sun. The earliest record of the age of the earth appears in the “Bible”, but the description in the calculation does not specify how old the earth is. Later, an archbishop of Ireland It is calculated that the earth originated at 6 pm on the 22nd, 4000 BC.
The archbishop spent a lot of brains to calculate the earth, and it was accurate to the hour. Perhaps such an answer was recognized by many people at the time. After all, this answer seemed so true. Of course, now we all understand that this is a wrong answer and it is very ridiculous.
Later, archaeologists tried to explore the age of the earth through biological fossils, which may not be a good method, and provided an inspiration for scientists at the time. But we all understand that the age of life on the earth does not represent the true age of the earth. The birth time of life must be less than the birth time of the earth. What’s more, the biological fossils we discovered through the discovery are not the earliest biological fossils on the earth, the earliest creatures. Fossils have long disappeared in the long river of history.
Scientists have collected a large number of paleontological fossils and found that the age of the earth is 75,000 years old. Of course, this is also a wrong answer. Later, physicists proposed to use a more scientific method to determine the age of the earth, that is, to calculate through the cooling of underground magma and the rate of heat dissipation on the surface. It seems that there is a certain scientific reason, but because we can’t really understand it. The true temperature of the core magma, the final result is also far from the true answer.
What really opened a new door for scientists to calculate the true age of the earth was the discovery of radioactive elements. Speaking of radioactive elements, we would think of couples living together. In 1898, the Curies discovered the radioactive elements polonium and radium, and at the same time discovered that radium is decaying. A lot of heat will be released at the time. The discovery of radioactive elements allowed scientists to find a new way to determine the age of the earth.
In 1904, Rutherford published a report on the influence of radioactivity on the temperature and age of the earth. He believed that the radioactive elements inside the earth could produce heat to balance its own cooling, and thus created a new field, radioactive earth age determination.
Through this method, scientists finally calculated the true age of the earth to be about 45.5±70 million years. Careful friends will find that this age is very consistent with the age of the sun. Is this a coincidence? Maybe not. The energy source inside the sun is actually very similar to the energy source inside the earth.
Radioactive elements release energy, and there is a large amount of uranium in the earth’s interior, and their decay also generates heat. Since the interior of the earth is a closed environment, it is difficult for this heat to radiate, and it gathers in the core of the earth to form a molten state, forming a high-temperature world with a temperature as high as 6000 degrees Celsius, which is very close to the temperature of the sun’s surface.
In addition, part of the heat of the earth’s core comes from the collapse of the earth’s gravity. A high-temperature core in a molten state contains a large amount of iron and nickel. They are all electrical conductors. Together with the induction of the solar wind on the earth, a strong magnetic field is formed to protect the earth. Of course, this is only a guess at present, and scientists are still unable to give a definite answer as to how the earth’s magnetic field came from.
Regardless of the formation mechanism of the earth’s magnetic field, there is no doubt that it must be related to the molten state of the earth’s core. If the earth’s core keeps cooling and finally becomes a solid state, the earth’s magnetic field will probably disappear. So will the inner core of the earth cool down one day? The answer is yes.
The main source of heat in the earth’s inner core is the decay of uranium or the continued decay of its decay products. The half-life of uranium-238 is 4.47 billion years and that of uranium-235 is 700 million years. The decay of these radioactive elements has basically been more than half. , And the next cycle will become shorter. So theoretically speaking, the inner core will get colder and colder, and it will be completely cooled in another 2.3 billion years. At that time, the earth’s magnetic field will disappear.
Without the protection of the magnetic field of the earth, life on the surface cannot survive, and humans will have to abandon the earth to live on other planets at that time. Of course, this time is still extremely long. 2.3 billion years are enough to allow human technology to develop to a height that we can’t imagine. Maybe it won’t take such a long time for human beings to walk all over the galaxy and even other galaxies in the universe. There will also be human figures, so we don’t have to worry that humans will have no place to live after the earth’s inner core has cooled.