Earth's magnetic field plays a crucial role in protecting life from radiation generated by the solar wind and cosmic rays. This invisible shield draws most of its power from a juggernaut "geodynamo," which is the mechanism that converts the kinetic energy of our planet's convective liquid outer core into magnetism. But Earth's lithosphere, meaning its crust and upper mantle, contains magnetic minerals that contribute a small boost to this defensive field. The lithosphere is, in turn, sculpted by the shifting polarity of Earth's magnetic activity over time. Scientists have been trying to better understand magnetic properties in the lithosphere for decades, but it can be challenging to detect the impact of the lithosphere's minor contribution to the field over the overwhelming flux produced by the core.

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