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Electromagnetic Coupling in Star-Planet Systems

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Handbook of Exoplanets

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Abstract

Most exoplanets are expected to be embedded in the flows of plasmas and the magnetic fields of their host stars. This setup enables powerful electromagnetic coupling mechanisms if the exoplanets are sufficiently close to their host stars. The coupling can result in large electromagnetic energy fluxes between the exoplanets and the stars possibly generating luminous effects on the stars. The root cause of the electromagnetic interaction and the resulting coupling is the relative motion of the exoplanet with respect to the magnetized plasma of the host star. Due to the large diversity of the exoplanets, e.g., distance to star, size, and the diversity of the host stars, e.g., stellar classes, the nature and the energy fluxes in the star planet interaction are expected to exhibit huge quantitative and qualitative variability. In this chapter, we introduce the basic setup of this coupling and the underlying physical mechanisms. We discuss various models of the electromagnetic coupling, such as the Alfvén wing model or models which describe the release of magnetic stresses, e.g., in coronal magnetic fields. We also briefly review the existing observational evidence for the star planet coupling and put it in context with theoretical expectations. We also compare the star planet coupling with the well-studied electromagnetic coupling between planets and moons in the outer solar system, e.g., Jupiter and its moon Io.

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Authors and Affiliations

  1. Institute of Geophysics and Meteorology, University of Cologne, Albertus-Magnus Platz, 50923, Cologne, Germany

    Joachim Saur

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  1. Joachim Saur
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Correspondence to Joachim Saur .

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Editors and Affiliations

  1. Instituto de Astrofísica de Canarias , La Laguna, Spain

    Hans J. Deeg

  2. Instituto de Astrofísica de Canarias, La Laguna, Spain

    Juan Antonio Belmonte

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Saur, J. (2017). Electromagnetic Coupling in Star-Planet Systems. In: Deeg, H., Belmonte, J. (eds) Handbook of Exoplanets . Springer, Cham. https://doi.org/10.1007/978-3-319-30648-3_27-1

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  • DOI: https://doi.org/10.1007/978-3-319-30648-3_27-1

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  • Print ISBN: 978-3-319-30648-3

  • Online ISBN: 978-3-319-30648-3

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