Science | Geophysics
Scientists propose that this occurs every 70 years and may influence the length of the day and the behavior of the planet’s magnetic field.
The depths of our planet still generate great doubts among scientists and the relationship between the inner core and the rest of the terrestrial layers remains unknown. This Monday, Yi Yang and Xiadong Song, researchers from Peking University, in China, point out in a
study published in the journal Nature Geoscience, that the inner core of the Earth has stopped rotating in the same direction as the rest of the planet, and could even be rotating to the other side, which may influence the length of the days and the the behavior of the planet’s magnetic field.
According to their conclusions, the rotation of the Earth’s inner core changes direction every few decades. This is possible because that iron ball as hot as the surface of the sun, the size of Pluto, which is more than 5,000 kilometers below our feet, floats in the liquid outer core and works almost independently, like a planet inside the planet.
Since we cannot reach the center of the Earth to study it in detail (the maximum depth reached is 12 km), the little that is known about the inner core comes from measuring seismic waves, created by earthquakes and, less frequently, by nuclear explosions. , because as these waves pass through the center of the Earth they reveal the internal composition of the nucleus and its speed of rotation.
The magnetic field protects Earth from solar winds.
If these radiation streams that
the Sun releases into space reach our planet, many species could disappear.
Cortex
Where is it
life
Outer core
liquid
Where is the magnetic field created?
The molten iron in the outer core generates electrical currents giving rise to a phenomenon called
geodynamo that produces the magnetic field.
Source: University of Rochester.
magnetic field
protects Earth from solar winds.
If these streams of radiation that the Sun releases into space
reach our planet, many species could disappear.
Cortex
where is life
Core
solid inside
composed of iron
and nickel.
Outer core
liquid
Where is the magnetic field created?
The cast iron of the outer core generates
electrical currents giving rise to a phenomenon called geodynamo that produces
the magnetic field.
Source: University of Rochester.
If these streams of radiation that the Sun releases
into space will reach our planet, many
species could disappear.
magnetic field
protects Earth from solar winds.
Cortex
Where is it
life
Core
solid inside
Composed of iron and nickel.
Outer core
liquid
where it is created
the magnetic field.
The cast iron of the outer core generates
electric currents giving rise to a
phenomenon called
geodynamo that produces
the magnetic field.
Source: University of Rochester.
If the core were inert, the seismic waves would not change, however, over time, they do. Song was one of the first to suggest, in 1996, that the inner core may be spinning at a different speed than the Earth’s surface. For this study, in collaboration with Yang, they analyzed seismic waves from 200 earthquakes in the South Sandwich Islands over the past six decades and found that the inner core’s rotation virtually stopped in 2009. Afterward, it began to rotate in the opposite direction. opposite the crust, from east to west.
controversial study
One possible explanation is that a fight is taking place between two great forces. On the one hand, the Earth’s magnetic field, which is created in the liquid outer core and which is closely linked to the presence of the Earth’s inner core, causes it to rotate. On the other hand, this impulse is counteracted by the mantle, whose gravitational field slows down this rotation movement. Thus, the researchers argue that there are physical links between all the layers of the Earth, from the inner core to the surface, and that this push and pull causes the inner core to rotate back and forth in a cycle of approximately 70 years.
If so, since there is some controversy regarding this theory, it seems that these changes would only affect the depths of our planet, but would not have a great impact on our lives. Perhaps subtle alterations in Earth’s magnetic field or in the length of days, which are known to rise and fall by a fraction of a millisecond every six years.
Despite everything, there is some controversy about these results and many researchers, unrelated to the Nature Geoscience study, have asked for caution about these findings, as there are still many unresolved doubts and data that require a more precise explanation.
#Earths #core #stopped #spin #reversed