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Related papers: Anelastic dynamo models with variable electrical c…

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We study the relationship of zonal gravity coefficients, J_2n, zonal winds, and axial moment of inertia (MoI) by constructing models for the interiors of giant planets. We employ the nonperturbative concentric Maclaurin spheroid (CMS)…

Earth and Planetary Astrophysics · Physics 2023-08-10 Burkhard Militzer , William B. Hubbard

We present the results of three-dimensional simulations of the deep convective envelope of a young (10 Myr) one-solar-mass star, obtained with the Anelastic Spherical Harmonic code. Since young stars are known to be faster rotators than…

Astrophysics · Physics 2008-04-03 Jérôme Ballot , Allan Sacha Brun , Sylvaine Turck-Chièze

(abidged) Context: Stellar convection zones are characterized by vigorous high-Reynolds number turbulence at low Prandtl numbers. Aims: We study the dynamo and differential rotation regimes at varying levels of viscous, thermal, and…

Solar and Stellar Astrophysics · Physics 2017-02-22 P. J. Käpylä , M. J. Käpylä , N. Olspert , J. Warnecke , A. Brandenburg

We study the effect of a massive planetesimal disk on the dynamical stability of the outer planets assuming, as has been suggested recently, that these were initially locked in a compact and multiresonant configuration as a result of…

Earth and Planetary Astrophysics · Physics 2015-05-20 Mauricio Reyes-Ruiz , Hector Aceves , Carlos E. Chavez

Jupiter's gravity field observed by NASA's Juno spacecraft indicates that the density in the 10--100 GPa region is lower than one would expect from a H/He adiabat with 0.5-5x solar water abundance as has been observationally inferred in…

Earth and Planetary Astrophysics · Physics 2025-04-02 Nadine Nettelmann , Jonathan J. Fortney

We conduct an in-depth analysis of statistical flow properties calculated from the reference high-resolution Saturn simulation obtained by global climate modelling in Part II. In the steady state of this reference simulation, strongly…

Earth and Planetary Astrophysics · Physics 2020-01-09 Simon , Cabanes , Aymeric , Spiga , Roland , M. B. Young

Uranus and Neptune are still poorly understood. Their gravitational fields, rotation periods, atmosphere dynamics, and internal structures are not well determined. In this paper we present empirical structure models of Uranus and Neptune…

Earth and Planetary Astrophysics · Physics 2022-03-14 Benno A. Neuenschwander , Ravit Helled

Increasing evidence is becoming available about not only the surface differential rotation of rapidly rotating cool stars but, in a small number of cases, also about temporal variations, which possibly are analogous to the solar torsional…

Astrophysics · Physics 2009-11-10 E. Covas , D. Moss , R. Tavakol

Numerous numerical studies have been carried out in recent years that simulate different aspects of exoplanets' magnetosphere and stellar winds. These studies have focused primarily on hot Jupiters with sun-like stars. This study addresses…

Earth and Planetary Astrophysics · Physics 2024-04-23 Fatemeh Bagheri , Ramon E. Lopez , Kevin Pham

(Abridged) The upper atmospheres of close-in gas giant exoplanets are subjected to intense heating/tidal forces from their parent stars. Atomic/ionized hydrogen (H) layers are sufficiently rarefied that magnetic pressure may dominate gas…

Earth and Planetary Astrophysics · Physics 2015-05-20 George B. Trammell , Phil Arras , Zhi-Yun Li

This paper presents scale invariant/self-similar galactic magnetic dynamo models based on the classic equations, and compares them qualitatively to recently observed magnetic fields in edge-on spiral galaxies. We classify the axially…

Astrophysics of Galaxies · Physics 2021-11-03 R. H. Henriksen , Judith Irwin

We explore kinematics and morphologies of molecular outflows driven by young protostars using magnetohydrodynamic simulations in the context of the unified wind model of Shang et al. The model explains the observed high-velocity jet and…

Solar and Stellar Astrophysics · Physics 2015-12-16 Liang-Yao Wang , Hsien Shang , Ruben Krasnopolsky , Tzu-Yang Chiang

The atmospheres of the four giant planets of our Solar System share a common and well-observed characteristic: they each display patterns of planetary banding, with regions of different temperatures, composition, aerosol properties and…

Earth and Planetary Astrophysics · Physics 2020-01-07 Leigh N. Fletcher , Yohai Kaspi , Tristan Guillot , Adam P. Showman

The numerical simulations of planetary dynamos still operate in a regime very far from the planets. For example, it seems unlikely that viscous forces are at all significant in planetary interiors, yet some of the simulations display a…

Earth and Planetary Astrophysics · Physics 2015-06-18 P A Davidson

Magnetic fields of low-mass stars and planets are thought to originate from self-excited dynamo action in their convective interiors. Observations reveal a variety of field topologies ranging from large-scale, axial dipole to more…

Solar and Stellar Astrophysics · Physics 2015-06-04 Martin Schrinner , Ludovic Petitdemange , Emmanuel Dormy

Magnetic fields, which are undoubtedly present in extragalactic jets and responsible for the observed synchrotron radiation, can affect the morphology and dynamics of the jets and their interaction with the ambient cluster medium. We…

High Energy Astrophysical Phenomena · Physics 2012-09-13 V. Gaibler , M. Krause , M. Camenzind

When our Sun was young it rotated much more rapidly than now. Observations of young, rapidly rotating stars indicate that many possess substantial magnetic activity and strong axisymmetric magnetic fields. We conduct simulations of dynamo…

Solar and Stellar Astrophysics · Physics 2010-11-15 Benjamin P. Brown , Matthew K. Browning , Allen Sacha Brun , Mark S. Miesch , Juri Toomre

Coronal jets are collimated, dynamic events that occur over a broad range of spatial scales in the solar corona. In the open magnetic field of coronal holes, jets form quasi-radial spires that can extend far out into the heliosphere, while…

Solar and Stellar Astrophysics · Physics 2016-04-06 P. F. Wyper , C. R. DeVore

Stably stratified fluid layers are common in gaseous planets, stellar interiors, and planetary cores, and have long been considered incapable of sustaining dynamo action. Here, we show that semiconvection - driven by a destabilizing thermal…

Earth and Planetary Astrophysics · Physics 2025-11-26 Paul Pružina , David Cébron , Nathanaël Schaeffer

Layered semi-convection could operate in giant planets, potentially explaining the constraints on the heavy elements distribution in Jupiter deduced recently from Juno observations, and contributing to Saturn's luminosity excess or the…

Earth and Planetary Astrophysics · Physics 2017-10-30 Q. André , S. Mathis , A. J. Barker