How does the earth "escape in death"?Scientists have discovered new clues

The earth is the only celestial body known in the universe, and it is one of the biggest miracles in the universe.

However, hundreds of millions of years ago, the earth experienced a devastating disaster -the magnetic field almost disappeared, leaving only a pitiful 10%. You know, one important reason why Mars has no life is that Mars's magnetic field disappears "really", which cannot be exempted from the direct blow of the sun style. The latest studies from scientists and collaborators from the University of Rochester from the University of Rochester showed that the magnetic field of the earth mysteriously restored 550 million years ago, making the earth avoid the fate of Mars. Related research papers are published in the Nature Communications of "

What causes the magnetic field to rebound?

At about 1800 miles under our feet, the liquid iron rotated by the earth's nuclear rotation generates the magnetic field of the earth. This magnetic field is invisible, but it is essential to the life of the earth, because it protects the earth from the solar wind of the solar radiation. However, about 565 million years ago, the strength of the magnetic field dropped to 10%today. Fortunately, the magnetic field was mysteriously "rebounded" back, and the intensity was restored before the Cambrian explosion of multi -cell creatures on the earth. This "rebound" occurred in tens of millions of years -it was very fast in geological time scale -and consistent with the formation of the earth's solid core, which indicates that the kernel may be a direct reason.

Figure ｜ The internal structure of the Earth (Source: Wikipedia)

John Tarduno, a professor at the Department of Earth and Environmental Sciences at the University of Rochester, said, "The core is very important." Starting growth, the magnetic field will be re -generated. "Researchers have determined several critical dates of kernel history, including more accurate estimates for their age. This study provides a clue about the history and future evolution of the earth, how the earth becomes a livable planet, and the evolution of other planet evolution of the solar system.

Researchers at the University of Rochester used the ancient magnetic magnetic to determine these two critical dates in the history of the earth nuclear. They believed that the nuclear nuclear restored the magnetic field before the outbreak of life on the earth.

Decoding information in ancient rocks

Earth is the third planet in the solar system. The main body includes rock rings, mantles, molten metals, and mainland cores of solid metal metals.

Figure ｜ Solar system (Source: Wikipedia)

Due to the relationship between the magnetic field and the nuclear nuclear, scientists have been trying to determine how the Earth's magnetic field and earth nuclear have changed throughout the history of the earth for decades. Due to the location and extreme temperature of the material in the ground nucleus, they cannot directly measure the magnetic field. Fortunately, minerals that are moved to the surface of the earth contain tiny magnetic particles. These magnetic particles lock the direction and strength of the magnetic field when the mineral is cooled from the melting state. In order to better understand the age and growth of the kernel, the research team uses the magnetic strong meter (Squid) magnetic strong meter (Squid) magnetic strong meter in the laboratory to analyze the long stone crystals in the oblique long rock. These crystals have tiny magnetic needles, which are perfect magnetic recorders. By studying the magnetic field locked in the crystal (that is, the ancient magnetic), the researchers determined the two new and important dates in the history of the nuclear nuclear:

550 million years ago: 15 million years ago, the Earth's magnetic field almost collapsed, and it began to update quickly. The researchers attributed the rapid update of the magnetic field to the formation of the solid kernel. The kernel was charged with a melting external nuclear and restored the strength of the magnetic field. 450 million years ago: the kernel structure in growth changes, and the boundaries between the internal and external kernel form. Due to the structure of the surface plate, the changes of these kernels are almost the same time as the changes in the upper mantle structure.

Figure ｜ There is no ground nuclear; about 550 million years ago, the kernel began to grow; about 450 million years ago, the outermost layer and the internal kernel boundary were formed.

"Because we have more accurately circulating the age of the kernel, we can explore the fact that the current kernel is actually composed of two parts." Deep printed in the structure of the nucleus, "Tarduno said.

Avoid the fate similar to Mars

It is of great significance to better understand the dynamics and growth of the kernel and magnetic field. It can not only reveal the past and predicting the future of the earth, but also reveal the way other planets may form magnetic fields and maintain the conditions required for life. Researchers believe that taking Mars as an example, Mars once had a magnetic field, but later disappeared, making Mars easily be affected by the solar style, resulting in the no ocean on the surface of Mars. Although it is unclear whether no magnetic field will cause the earth to encounter the same destiny, the researchers said, "If the magnetic field of the earth does not regenerate, the earth will definitely lose more water." "The earth will be much dry than it is now, and it will be very different. "As far as planet evolution is concerned, this study emphasizes the importance of magnetic fields and the mechanism of maintaining magnetic fields. "This study does emphasize that there is something like an increased kernel, maintaining a magnetic field in the entire life cycle of the planet (billions)." Tarduno said. Reference link: https://www.nature.com/articleS/S41467-022-31677-7 Reprinted content only represents the author's point of view

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