Magnetic field strengths of hot Jupiters from signals of star–planet interactions

  title={Magnetic field strengths of hot Jupiters from signals of star–planet interactions},
  author={P. Wilson Cauley and Evgenya L. Shkolnik and Joe Llama and Antonino F. Lanza},
  journal={Nature Astronomy},
Evidence of star–planet interactions in the form of planet-modulated chromospheric emission has been noted for a number of hot Jupiters. Magnetic star–planet interactions involve the release of energy stored in the stellar and planetary magnetic fields. These signals thus offer indirect detections of exoplanetary magnetic fields. Here, we report the derivation of the magnetic field strengths of four hot Jupiter systems, using the power observed in calcium ii K emission modulated by magnetic… 
Magnetohydrodynamic modelling of star–planet interaction and associated auroral radio emission
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Low-frequency ( ν  ≲ 150 MHz) stellar radio emission is expected to originate in the outer corona at heights comparable to and larger than the stellar radius. Such emission from the Sun has been used
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Time-domain Modulation of HD 189733 Activities by Its Planet
  • Yang Gao
  • Physics, Geology
    The Astronomical Journal
  • 2021
Star–planet interaction can be studied by analyzing exoplanetary orbit and stellar rotation modulations of the transit emissions from exoplanetary systems. Here we carry out a time-domain analysis of


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This work reports an extension of a scaling law derived from geodynamo models to rapidly rotating stars that have strong density stratification, and predicts that the field strengths of rapidly rotating brown dwarfs and massive extrasolar planets are high enough to make them observable.
Estimating the magnetic field strength in hot Jupiters
A large fraction of known Jupiter like exoplanets are inflated as compared to Jupiter. These "hot" Jupiters orbit close to their parent star and are bombarded with intense starlight. Many theories
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Size and Strength of Self-excited Dynamos in Jupiter-like Extrasolar Planets
The magnetization of solar and extrasolar gas giants is critically dependent on electronic and mass transport coefficients of their convective fluid interiors. We analyze recent laboratory
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Stars interact with their close-in planets through radiation, gravitation, and magnetic fields. We investigate the energy input to a planetary atmosphere by reconnection between stellar and planetary
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We study the internal structure and the convective motions of giant extrasolar planets in order to calculate their dynamo-generated surface magnetic field and dipolar magnetic moment. Using
Assessing magnetic torques and energy fluxes in close-in star-planet systems
Planets in close-in orbit interact with the magnetized wind of their hosting star. This magnetic interaction was proposed to be a source for enhanced emissions in the chromosphere of the star, and to
Signatures of Star-planet interactions
Planets interact with their host stars through gravity, radiation and magnetic fields, and for those giant planets that orbit their stars within $\sim$10 stellar radii ($\sim$0.1 AU for a sun-like