You didn't feel the Earth moving and changing direction? Well, that's normal, because if the rotation of its core has indeed changed its trajectory, it is totally imperceptible to us living beings. A very serious study, published in the journal Nature Geoscience, suggests that the inner core of our planet iscurrently changing its direction of rotation. To simplify the phenomenon, according to Yi Yang and Xiaodong Song, the "seed" of the Earth would be subjected to a 70-year cycle and would change its direction of rotation every 35 years.
But to tell the truth, we still do not know all the secrets of our core to this day. Scientists are trying to unravel its mysteries, while it remains impossible for humans to access. To imagine, this huge ball with a diameter of 2446km rotates on itself at 5000km under the ground we walk on. This inner core, discovered in 1936, is composed of an alloy of iron and nickel, where the temperature is around 5500 degrees. It is therefore inaccessible.
This metallic core is constantly subjected to the pressure of the Earth's magnetic field and its mantle, which perform an exceptional arm wrestling. According to scientists, it does not follow the direction of rotation of the Earth and does not have the same speed, because the seismic waves change direction with time. They have studied these waves since the 1960s, the only way to access the core at present. According to them, the "seed" was stationary in 1970, before starting to turn eastward, then slowing down and stopping between 2009 and 2011. Since then, it has started to turn west again and should stop again in 2040, before venturing in the other direction.
For the moment, scientists lack data, we will have to wait about 50 years to verify if this theory is correct. In the meantime, there are still many mysteries to solve!
