Researchers from the University of Texas at Austin have presented new findings about the Earth’s metallic core, suggesting it is softer than scientists once believed. The study appears in the scientific journal Earth, Atmospheric and Planetary Sciences (EAPS).
At the earth’s center sits a metal sphere primarily made of iron, with a diameter of about 1,220 kilometers. This inner core is encased by an outer core, a churning ocean of liquid metals that sits beneath a vast mantle, which itself lies beneath the planet’s solid crust. For a long time, scientists reasoned that the immense pressures inside the inner core would lock the material into a completely solid state.
To test that assumption, the team simulated the extreme pressures found at the core inside a laboratory setting and observed how iron behaves under those conditions. The observations were then fed into computer models to predict how the core would respond in reality. The results showed that iron atoms remain in active motion, indicating that the inner core is not a rigid monolith. Instead, atoms shift among different positions, while the overall crystal lattice remains intact. This reveals a more dynamic interior than previously imagined.
Experts say this revised picture of the core could improve our understanding of the processes that generate and sustain Earth’s magnetic field, which shields the planet from solar radiation. The magnetic field is a crucial feature for life on Earth and has implications for navigation, satellite operations, and terrestrial technology.
Earlier inquiries mentioned sizable anomalies deep beneath New Zealand, hinting at complex underground processes. The new results add to a growing body of evidence that the planet’s core behaves in a more nuanced way than a strictly solid model would allow, offering fresh avenues for research and inquiry across geophysics and planetary science.