Scientists claim to have solved a 300-year-old riddle about the direction in which the centre of the Earth spins.
The Earth’s inner core, made up of solid iron, ‘super rotates’ in an eastward direction — meaning it spins faster than the rest of the planet, scientists at the
University of Leeds found.
Meanwhile, the Earth’s outer core, comprising mainly molten iron, spins westwards at a slower pace.
Although Edmund Halley had showed the westward-drifting motion of the Earth’s geomagnetic field in 1692, it is the first time that scientists have been able to link the way the inner core spins to the behaviour of the outer core.
The planet behaves in this way because it responds to the Earth’s geomagnetic field.
The findings will help scientists to interpret the dynamics of the core of the Earth, the source of our planet’s magnetic field. In the last few decades, seismometers measuring earthquakes travelling through the Earth’s core have identified an eastwards, or super rotation of the solid inner core, relative to Earth’s surface.
“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,” said Dr Philip Livermore, of the University of Leeds.