Scientists have long known that the Earth’s inner core is a hot, dense ball of metal, surrounded by an outer core of molten iron. But new research reveals that this inner core is not only spinning in a different direction, but also changing shape.
For decades, researchers have suspected the inner core might deform over time. A new study published in Nature Geoscience now supports this theory, with scientists analyzing seismic waves from powerful earthquakes.
CTV science and technology expert Dan Riskin spoke with CTV Your Morning on Monday to discuss this recent discovery and how it could affect the long-term health of both Earth and humanity.
“There are these earthquake sensors in Alaska and the Yukon that have been measuring earthquakes from the South Sandwich Islands over decades,” Riskin said. “The South Sandwich Islands are near Antarctica, so every time there’s an earthquake down there, it sends a signal.”
Riskin says by measuring the difference between what you hear in Alaska and what you hear in the Yukon, with some waves going through the core and some just barely missing it, “you can start to measure what the core looks like.”
The seismic waves show that the outermost layer of the inner core may be more flexible than the deeper layers. Riskin says tracking these changes could save our lives, as the inner core’s movement plays a crucial role in generating the Earth’s magnetic field, which shields us from harmful solar radiation. That’s why Sun’s radiation turns into northern lights and does not kill us, Riskin explains.
“Mars doesn’t have that. It used to have an atmosphere, and this solar wind just ripped the atmosphere off and blew it into space,” Raskin said. “That would happen to us if our core is not doing its job properly.”
Raskin adds that while there’s no indication there’s anything wrong, it’s vital that scientists stay on top of any changes going forward.
“We really do want to understand it, because it keeps us alive.”
