Scientists in China recently made a discovery at the heart of our planet: Every 8.5 years, the Earth's inner core wobbles around its rotational axis. This shift is likely caused by a tiny misalignment between the inner core and the Earth's mantle—the layer below the Earth's crust, according to the researchers' new study.
Starting around 1,800 miles (2896 km) beneath the surface, Earth's core is split into a swirling liquid outer boundary and a mostly solid inner layer. This region is partially responsible for a number of our planet's geophysical dynamics, from the length of each day to Earth's magnetic field, which helps protect humanity from harmful rays emitted by the sun.
