Very old earth. It is an old enough to give a few-generations of the mountains that have gradually eroded. It is enough to let the drifted continent to drift more than 100 times, enough to create a wide variety of life, these Life includes an occasional will stop standing, thinking about this world has an ancient creature. According to the current scientific inference, our planet has about 454 billion years, this number is not big. But if it is contemplated, this is a long dizziness of 454 billion years. Only in the 1950s, scientists were able to draw a reliable data on the earth's birthday. The ancient ancient imaginations of the earth, this is a lot of thinkers' great horror, and they also think about the position of human beings in the universe. Humans have long known that this world is very old, but they didn't expect to be so old. Early Early Exploring Religious Schemes Many Human Civilization did not try to explore the birth time of the earth, because their time concept is round. For them, there is no beginning, no end, it is just a cycle that is unhappy. For the Greeks and ancient India, the world will always be born and regenerated in endless destruction and rebirth. Linear time concepts with starting and ending are later begun to accept people. It comes from the development of Judaism and Christian ideas. The Bible said, at first, God created the world. So, ask "when?" Is just a natural thing. Exploring the starting point of the world belongs to the scope of religion, rather than science. However, since scientists show their observations and reasoning skills in revealing the secrets of nature, some people have increased, and they are beginning to seek clues from the Earth age outside the Bible. Salt clock They need a natural timer, a clock that starts from the birth of the Earth. More accurately, they need to find a natural process that occurs at a known speed, the current state of the process ("Take"), which can be compared to the state of the Earth ("before"). In 1715, the British Astronomer Edon, who was known to find Harley, and Harley proposed that the ocean may be such a hour. He inferred that the salt water was originally freshwater. After a long time, it turned into salt water because the salt was brought into the sea. If someone is enough to measure the sailing speed of the sea, this is possible to determine the age of the ocean in accordance with the concentration of sea water today and the age of the Earth is possible. Harley did not have this measurement in him. Even if he has tried it, the change in sea water is too fine, and the method he can try is unbearable. Moreover, his idea contains a fatal defect, because the salt that is frushed to the sea is no longer changing there, it may be buried in the sediment, or returned to the land with rainwater waves. Harley's "Salt Bell" is therefore delayed, and later when scientists try this method, they estimate that the earth is less than 100 million, too young. The hot clock is more hopeful than the salt clock is "hot clock". In 1687, Newton noted that a molten rock or metal cooled at a predictable speed, and the cooling rate depends on its diameter. Due to the diameter of the earth, his internal temperature can be estimated by measuring the temperature of the hot springs and deep mines, and the time to calculate the time of the earth's lava begins to cool. The 19th century scientist first tried to calculate the Earth's cold when the hot clock was calculated, and the answer they got was 75,000 years. But many scientists believe that this number seems too much. Geologists pointed out that there is a concentrated deposit layer in the mountain range such as the Alps.
These sediments are slowly accumulated in ancient oceans, and then rushed to form a mountain range due to changes in terrain. This process is obviously a time, 75,000 years is not enough. Later, the improvement of the hot clock increased the estimation of the Earth's age, reached tens of millions of years, which compared to the requirements of the geologist, although some people still be unsatisfactory. In 1862, the British physicist William. Thompson (he is more known to Karlin Lord), according to the principle of the hot clock, the age of Earth will not exceed 100 million years. Kelwin may be the most respected scientist in the 19th century, so most geologists have accepted his estimate. Even when he made his estimate is only 24 million years, almost no one will give an objection. However, a group of scientists did this. They are a batch of biologists headed by Charlie. Darwin, Darwin's thoughts on evolution and slow transformation of species, need a lot of time. For decades, evolutionists and physicists can be used for the longitude of the species evolution. In 1882, Darwin died, he didn't know if his theory can be tested. Until the time of the century, people know that biologists are right, physicists are wrong. There is a shortcoming of the hot clock. Like the salt clock, it underestimates the age of the earth. Our calorie is not as long as people, but in contrast, due to internal radioactive energy, the heat of the earth is constantly supplemented. The heat generated by the radioactive circle decay in the Earth will not succeed. But for those who study the history of the earth, radioactive discovery is far from bad news. Instead, it provides them with the latter to find a natural clock. Radioactive decay reveals the secret of Earth's age in early 20th century, physicists conducted the first attempt to determine the rock radioactive ingredients, and the results of the resulting results were unable to believe. This approach shows that the age of the earth will be tens of millions of years from time to time. At that time, people's understanding of the radiation was still very small, and several famous geologists were disclosed, they would like to know that the physicist is not wrong this time. But this time they are right. The method of using radioactivity determination rock and other objects (referred to as the radioactive measurement age) is known as one of the most confirmed technologies in the scientific community. Earth is a changing planet. The original crustal rock has been crushed or melted because of the mountain movement, or because of the wind erosion. According to the radiological age calculation algorithm, the oldest rock known from the Earth (from Canada to Greenland) is approximately 39 billion years. But they can't be the remains of the original earth, because many such rocks are sedimentary rocks such as sandstone, which is obviously from erosion from the ancient rocks. The oldest ore is more than 4 billion years, is it the age of the earth? No, because other places in our solar system have discovered an older rock, astronomers know that the entire solar system is formed at the same time, but the rock housing of the Earth seems to be destroyed by the whole. The evidence found from the space is largely filled with this gap. When a rotent cloud composed of dust and gas is condensed, the earth, the moon, and the planet are also formed at approximately one time. Since the moon and the asteroid are much smaller than the earth, the heat is not enough, and it cannot be keryled inside, and the destruction of the mountain movement cannot be formed. Therefore, the geologist speculates that the original rock may be present on these universal stars. Sure enough, the moon rock brought back to the "Apollo" spaceship astronaut found that these rocks are very old. The oldest rock is about 45 billion years. The earth has entered into the middle-year of most of the meteorite of asteroid debris is similar to the moon rock.
