(CNN) — Deep inside Earth is a solid metal ball that rotates independently of our spinning planet, like a top whirling around inside a bigger top, shrouded in mystery. This inner core has intrigued ...

More than 5,000 kilometres beneath us, Earth’s solid metal inner core wasn’t discovered until 1936. Almost a century later, we’re still struggling to answer basic questions about when and how it first ...

Earth’s inner core has long challenged researchers because seismic waves do not move through it uniformly. Compressional waves generated by earthquakes travel roughly 3 to 4 percent faster along Earth ...

Earth's inner core is solid and blistering hot. For decades, scientists have known the inner core is solid thanks to the pioneering work of Danish seismologist Inge Lehmann, who first proposed its ...

Earth's inner layers have just got a bit more complicated, with scientists discovering a whole new inner core within the center of the planet. Research released on February 21 in the journal Nature ...

More than 5,000 kilometers beneath us, Earth’s solid metal inner core wasn’t discovered until 1936. Almost a century later, we’re still struggling to answer basic questions about when and how it first ...

The rotation of the Earth's inner core may be reversing, scientists have found in a study that sheds new light on geological processes occurring deep within our planet. The results of the research, ...

If the core froze relatively recently, the current thermal state at the inner core–outer core boundary indicates how much the combined core might have been below its melting point when the inner core ...

"We might have volcanoes on the inner core boundary, for example, where solid and fluid are meeting and moving," he said. Because the spinning of the inner core affects movement in the outer core, ...

More than 5,000 kilometers beneath us, Earth's solid metal inner core wasn't discovered until 1936. Almost a century later, we're still struggling to answer basic questions about when and how it first ...