The Earth’s core is actually solid.
A new study by scientists from the Australian National University may help us understand how our planet was formed.
Scientists believe that they have evidence that the Earth’s inner core is solid.
They invented a way of recording shear waves in the Earth’s core, and such waves can be observed only in solid objects.
“We found out that the Earth’s core is indeed solid, but also found that it is much softer than previously thought. If our results are true, then its elastic properties similar to gold and platinum. – says head of research, Professor Hrvoje Gefle if. – The Earth’s core like a time machine, and if we study him, we will understand how our planet was formed and how it evolved”.
Shear waves in the Earth’s core is so weak that to detect them directly, and their search was the “Holy Grail” of global seismology with ever since scientists first predicted that the core is solid even in the 1930s – 1940s. Therefore, the researchers had to approach the matter creatively.
The so-called method of correlation of the wave field looks at the similarity of the signals from the two sensors after the great earthquake, than the direct signals of the waves. A similar technique was used by the same team in the measurement of ice thickness in Antarctica. In the access of scientists had all the sensors and all the big earthquakes on Earth.
The study showed that these results can be used to prove the existence of transverse waves and their propagation speed in the earth’s core. Moreover, this information can give us to understand what is the core temperature, what is his age, or how fast it hardens.