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Simple Estimations for Planetary Convection Turbulence and Dynamo Magnetism from Optimized Scaling and Observations

  • S. V. Starchenko
Conference paper
Part of the Springer Geophysics book series (SPRINGERGEOPHYS)

Abstract

My optimal similarity factors allow arguing the planetary turbulent convection to be close to its critical level with turbulent transport coefficients higher than the molecular values. These strongly simplify numerical models for the primordial and recent convection and correspondent magnetic field of the planets and moons. Mean arithmetic magnetic field in the dynamo region is well defined by the observable magnetic dipole. The Earth, Jupiter and Saturn have that mean fields of order 1 mT and small inclination of their dipoles to the axis of rotation. Thus, similar dynamo models are successful for those planets. The Uranus and Neptune also have ~1 mT, but their dipoles are strongly inclined requiring some modifications in dynamo modeling. The major problems are posed by too small and asymmetric magnetic field in Mercury/Ganymede and absence of an active dynamo in Venus/Mars.

Keywords

Planetary interiors Convection Turbulence MHD dynamo Magnetism 

Notes

Acknowledgements

Author is deeply grateful to the anonymous reviewer and to Prof. Dmitry Sokoloff for their constructive criticism that resulted in sufficient improving of this work. This work was basically done under IZMIRAN budget. The work was also partly supported by the Russian Foundation for Basic Research (project no. 16-05-00507a) and 28th program of the presidium of Russian Academy of Sciences.

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences (IZMIRAN)Troitsk, MoscowRussia

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