Every so often a mysterious 'jerk' rumbles through our planet's magnetic field lines, roughly every 10 years – and scientists might now know why.
It's to do with the liquid metal inside our planet which generates the magnetic field.
Researchers believe that the 'jerks', which were first detected in 1978, come from rapid spurts of hot metal in the Earth's core.
Researchers at the Institut de Physique du Globe de Paris and the Technical University of Denmark used supercomputers to model the movement of metal in the core.
The models suggest that the 'jerks' are linked to 'sudden buoyancy releases' in the core, sudden releases of heat within the core.
The researchers say that the find could help us further understand the mysteries of the Earth's core.
The researchers write, 'The ability to numerically reproduce jerks offers a new way to probe the physical properties of Earth's deep interior.'
- This article first appeared on Yahoo
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