The heart of the Earth swings like a top!

The Earth rotates on its axis, and all the geological atmospheres of which it is composed rotate with it. However, it appears that the rotation of these different layers is not completely synchronized. Previous studies have actually shown that the inner core rotates at a different speed than the outer shells. a a movementa movement The differential that is involved in generating the Earth's magnetic field.

Johar does whatever he wants!

A new study reveals that the inner core is also oscillating. In other words, seeds ironiron solidsolid The one at the center of the Earth behaves a bit like a peak about to stop. Researchers have just confirmed that the inner core oscillates around its axis of rotation periodically, following cycles lasting about 8.5 years. The results were published in review Nature Communications.

Additional constraints on the dynamics and structure of the inner core

This 8.5-year signal was previously discovered during studies related to the movement of the poles, the periodic motion of the Earth's rotation axis and changes in day length. These data indicate that the inner core was driven by its own oscillation, different from that in the Earth's mantle. And so the researchers created a lighta light A shift of less than one degree in the alignment of the rotation axes between these two Earth's atmosphere. These results also allow the identification of density heterogeneity within the inner core itself, providing significant constraints on seed stratification. And so it seemsNorthern hemisphereNorthern hemisphereThe western inner core is denser than its other regions.