Study resolves Earth's geodynamo paradox by directly measuring thermal conductivity of iron at planetary core conditions for the first time, indicating that Earth’s geodynamo has persisted since the beginning of Earth’s history, and allowing for a solid inner core as old as the dynamo.

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Study resolves Earth's geodynamo paradox by directly measuring thermal conductivity of iron at planetary core conditions for the first time, indicating that Earth’s geodynamo has persisted since the beginning of Earth’s history, and allowing for a solid inner core as old as the dynamo.