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A magnetically driven equatorial jet in Europa’s ocean

Nature Astronomy (2019) | Download Citation

Abstract

During recent decades, data from space missions have provided strong evidence of deep liquid oceans underneath a thin outer icy crust on several moons of Jupiter1,2, particularly Europa3,4. But these observations have also raised many unanswered questions regarding the oceanic motions generated under the ice, or the mechanisms leading to the geological features observed on Europa5,6. By means of direct numerical simulations of Europa’s interior, we show here that Jupiter’s magnetic field generates a retrograde oceanic jet at the equator, which may influence the global dynamics of Europa’s ocean and contribute to the formation of some of its surface features by applying a unidirectional torque on Europa’s ice shell.

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The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.

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Acknowledgements

The GO-J-MAG-3-RDR-HIGHRES-V1.02 dataset was obtained from the Planetary Data System. This work was granted access to the HPC resources of MesoPSL financed by the Region Ile de France and the project Equip@Meso (reference ANR-10-EQPX-29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche.

Author information

Author notes

  1. These authors contributed equally: Christophe Gissinger, Ludovic Petitdemange.

Affiliations

  1. Laboratoire de Physique de l’Ecole Normale Superieure, ENS, Université PSL, CNRS, Paris, France

    • Christophe Gissinger
  2. LERMA, CNRS, Paris, France

    • Ludovic Petitdemange

Authors

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Contributions

C.G. conceived the presented idea and developed the theory. L.P. performed the numerical simulations. C.G. and L.P. performed the analysis of the results and contributed to the final manuscript.

Competing interests

The authors declare no competing interests.

Corresponding author

Correspondence to Christophe Gissinger.

Supplementary information

  1. Supplementary Information

    Supplementary Table 1, Supplementary Figures 1–3.

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DOI

https://doi.org/10.1038/s41550-019-0713-3