Earth’s inner core may have quietly reversed course: after decades of spinning slightly faster than the surface, seismic waves from repeating earthquakes show it slowed around 2010 and began drifting backward relative to the rest of the planet. - Space Daily

More than 5,000 kilometres beneath your feet, Earth’s solid inner core has spent the past few decades turning slightly faster than the planet wrapped around it. Seismic measurements suggest that around 2010 it slowed to match the surface, and has since fallen…