Galileo Gravity Results and the Internal Structure of Io

  title={Galileo Gravity Results and the Internal Structure of Io},
  author={J. D. Anderson and William L. Sjogren and Gerald Schubert},
  pages={709 - 712}
Doppler data generated with the Galileo spacecraft's radio carrier wave were used to measure Io's external gravitational field. The resulting triaxial field is consistent with the assumption that Io is in tidal and rotational equilibrium. The inescapable conclusion is that it has a large metallic core. If the core is a eutectic mixture of iron and iron sulfide, it comprises 20.2 ± 7.4 percent of the satellite's total mass with a radius that is about 52 percent of Io's mean radius of 1821.3… 

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