300-Year-old Scientific Riddle Solved! Earth's Center Spins In An Eastward Direction

Researchers from the University of Leeds solved a 300-year-old scientific riddle by revealing that the Earth's center spins in an eastward direction.

The Earth's inner core is made up of solid iron and for over 300 years, scientists have wondered about which direction the planet's center spins in. In 1692, Edmund Halley revealed the westward-drifting motion of the Earth's geomagnetic field but it wasn't until recently that the riddle was solved.

Researchers from the University of Leeds revealed that  the Earth's center spins at a faster pace in an eastward direction while the outer core, which is made up of molten iron, spins at a slower pace in a westward direction. This study is the first to link the way the inner core spins to the behavior of the outer core.

"The link is simply explained in terms of equal and opposite action", explained Dr Philip Livermore, of the School of Earth and Environment at the University of Leeds. "The magnetic field pushes eastwards on the inner core, causing it to spin faster than the Earth, but it also pushes in the opposite direction in the liquid outer core, which creates a westward motion."

The inner core is the size of the moon and is surrounded by molten iron. The convection-driven movement of this iron alloy generates a geomagnetic field, which is responsible for the way the planet behaves in terms of movement. Owing to the fact that the Earth's internal magnetic field changes slowly over time, it also leads to change in the electromagnetic force responsible for pushing the inner and outer cores.

This can serve as an explanation as to why some previous studies suggested that drift direction has not always been westwards. Some prior observations have also noted an eastward direction of the Earth's outer core in the last 3,000 years.