How to locate the electrically conducting fluid core of a planet from external magnetic observations

Abstract

A NEW method is proposed here for locating the electrically conducting fluid core of a planet from external magnetic observations. When tested with the aid of geomagnetic data, the method gives for the radius of the Earth's liquid metallic core a value which differs insignificantly from the accepted value (based on seismic data). These findings have important implications for future investigations of the magnetic fields and internal structure and dynamics of the Earth, Jupiter, and other magnetic planets.