Scientists have detected a significant shifting inside Earth occurring deep beneath the planet’s surface near the core-mantle boundary, based on data from NASA satellites. This discovery reveals dynamic processes thousands of miles below that may influence Earth’s internal structure and magnetic shielding.
Discovery Through Satellite Gravity Data
A team led by geophysicist Charlotte Gaugne Gouranton from Paris City University analyzed data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellites covering 2006 to 2008. Although these satellites primarily monitor changes in groundwater and sea levels, the researchers used subtle variations in Earth’s gravitational field to detect unexpected mass shifts deep inside the planet. Their findings, published in Geophysical Research Letters, suggest that a massive movement of material occurred near the zone where Earth’s mantle meets its core.
Implications for Earth’s Interior and Magnetic Field
The study proposes that a mineral called perovskite, abundant in the lower mantle, underwent a structural phase change, causing nearby rocks to become denser and heavier. This denser material displaced mass, sending ripples through the surrounding layers and potentially affecting Earth’s core boundary. Understanding these deep shifts is critical because they could explain how Earth’s layers interact and contribute to sustaining the geomagnetic field that shields the planet from harmful solar and cosmic radiation.
Coauthor Isabelle Panet from University Gustave Eiffel emphasized that these connections between Earth’s interior layers are vital to comprehending the planet’s geodynamics and magnetic field maintenance. The discovery of such deep, large-scale shifts challenges previous assumptions that Earth’s interior is relatively stable on short timescales, revealing an active, evolving planet beneath our feet.