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AsteriaStar
Interior layer

Core

The dense central region of a planet or moon, typically the heaviest material that sank inward as the body formed. In the terrestrial planets it is largely iron; where it is partly molten and convecting, as in Earth, it can generate a global magnetic field.

Highlights

  • Where a planet's magnetic field is born

Across comparative planetology

Knowledge connections

Sources

The primary and reference sources this topic draws on.

  • NASANational Aeronautics and Space Administration

    Mission data, planetary science, space telescopes, and public-domain imagery.

    Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.