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A team of scientists conducted a laboratory experiment high accuracy, during which it determined the melting point of iron, of which the solid inner earth core partly consists. Using this data, the researchers calculated the temperature on the boundary between the inner solid and the outer liquid core. It turned out that it is equal to the temperature on the surface of the Sun, that is, is about 6000 degrees Celsius. This difference matters to geophysics, because it explains the mechanism of magnetic field generation Of the earth. The core consists of two parts: internal solid and external liquid. The latter, in turn, borders on a solid, but unsteady the mantle. The temperature difference between the inner solid core and the mantle should be around 1500 degrees Celsius in order to provoke the so-called thermal motion – the reason for the formation of magnetic fields of the planet. Previous studies have shown that the difference insufficient temperatures, and this was a real paradox in science. According to 1990 data, the core temperature should be 5,000 degrees Celsius. In the latest experiment on the study of the earth’s core and its temperature took part researchers from the french national research CEA Center, CNRS National Research Center and European synchrotron ESRF. At the synchrotron were used x-rays with which you can make very quickly. Time in this case plays a big role for scientists, so how pressed iron samples in a laboratory usually “live” in total few seconds. Because of this, it was previously very difficult to determine whether metal began to melt or is still solid condition. The study using synchrotron radiation allows very accurately determine at what temperature rearrangement (melting) of the iron crystal lattice. IN synchrotron researchers sent x-rays to heated up to 3000-5000 degrees iron samples compressed between two diamonds (thus creating a pressure of two million atmospheres, as in bowels of the Earth) and observed a change in direction of movement “translucent” of their rays. The moment the metal melts the structure of its crystal lattice also changes, as a result of which the diffraction pattern fixed by the instruments also changes (diffraction). Since temperature and pressure are also recorded instruments, scientists were able to very accurately determine the temperature melting samples. It turned out that iron in a solid earth core melts at a temperature of 4800 degrees Celsius and a pressure of 2.2 times the pressure on the surface of the Earth. Thus, scientists concluded that the temperature at the border of internal and external the core should be 6,000 degrees Celsius, and the pressure should be around 3.3 million atmospheres. According to study co-author Agnes Deval (Agnes Dewaele), now it all fits together. Research results geophysicists were published in the journal Science.
