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3 - The Interior of Saturn

Published online by Cambridge University Press:  13 December 2018

Kevin H. Baines
Affiliation:
University of Wisconsin, Madison
F. Michael Flasar
Affiliation:
NASA-Goddard Space Flight Center
Norbert Krupp
Affiliation:
Max-Planck-Institut für Sonnensystemforschung, Göttingen
Tom Stallard
Affiliation:
University of Leicester
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Summary

We review our current understanding of the interior structure and thermal evolution of Saturn, with a focus on recent results in the Cassini era. There has been important progress in understanding physical inputs, including equations of state of planetary materials and their mixtures, physical parameters like the gravity field and rotation rate, and constraints on Saturnian free oscillations. At the same time, new methods of calculation, including work on the gravity field of rotating fluid bodies, and the role of interior composition gradients, should help to better constrain the state of Saturn’s interior, now and earlier in its history. However, a better appreciation of modeling uncertainties and degeneracies, along with a greater exploration of modeling phase space, still leave great uncertainties in our understanding of Saturn’s interior. Further analysis of Cassini data sets, as well as precise gravity field measurements from the Cassini Grand Finale orbits, will further revolutionize our understanding of Saturn’s interior over the next few years.

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Publisher: Cambridge University Press
Print publication year: 2018

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