Scientists have detected strange “signals” coming from Earth, which repeat every seven years, adding a new mystery about the Earth’s magnetic field.
Nicholas Gillett and a team from the University of Grenoble Alpes have observed the behavior of the magnetic field around the equator for 22 years and found that every seven years, the magnetic field fluctuates at 900 mph.
Gillette’s search for strange signals passing through the magnetic field is a window into the undiscovered center of the Earth.
“Understanding those signals opens a door to what’s going on deep in the Earth, and we can’t investigate that directly, based on observations alone,” Gillette told Newsweek.
The center of the Earth’s core lies roughly 4,000 miles from the surface, a bewildering ball of densely packed iron with a temperature of up to 10,000 degrees Fahrenheit.
It swirls around the inner core, the outer core which is molten liquid metal, which has a temperature of 5,000 degrees.
According to New Scientist, the temperature difference between the two forces acts on the liquid outer core, causing charged particles to create the magnetic field that surrounds Earth (this and the Earth’s rotation also cause the liquid outer core to ripple).
The idea of a solid layer of rock was useful in modeling the behavior of the magnetic field, and Gillette’s findings support a long-standing theory that there is a layer of rock between the mantle and the liquid outer core.
Their research, says Gillette, adds more doubt to the solid’s existence, given that the core is needed to generate the magnetic field, which does more than just conduct energy.