Abstract—For the case of the sub-Alfvén regime of the stellar wind flyby around the planet, the flow structure in the vicinity of a hot Jupiter have been studied by three-dimensional numerical simulation. As an example, the hot Jupiter HD 209458b was considered. The planet’s magnetic moment was set equal to 10% of the magnetic moment of Jupiter. The average magnetic field at the parent star’s surface was taken to be 0.5 G, corresponding to a relatively strong wind field. Under such conditions, calculations have shown that a quasi-closed ionospheric (gas) envelope with an induced shockless magnetosphere forms around a hot Jupiter. Under the influence of the strong magnetic field of stellar wind, envelope matter outflowing from the inner Lagrange point does not move along the ballistic trajectory, but rather moves along magnetic field lines of the wind toward the star. Therefore, for the sub-Alfvén flow regime, a new ionospheric envelope type of hot Jupiters is considered to be discovered, supplementing the classification suggested earlier based on results of purely gas-dynamic modeling. Possible distinctive features of the observational manifestations of such envelopes are discussed.

摘要-对于恒星绕过行星的亚Alfvén体制，通过三维数值模拟研究了热木星附近的流动结构。例如，考虑了热的Jupiter HD 209458b。行星的磁矩设定为等于木星磁矩的10％。母星表面的平均磁场取为0.5 G，相当于一个相对强的风场。在这样的条件下，计算表明，在热木星周围形成了一个准封闭的电离层（气体）包膜，形成了感应无磁层。在恒星风的强磁场的影响下，从内部拉格朗日点流出的包膜物质不会沿着弹道运动，而是沿着风的磁力线向恒星移动。因此，对于亚Alfvén子流态，考虑发现一种新的电离层包层类型的热木星，补充了先前基于纯气体动力学模型结果建议的分类。讨论了这种信封的观察表现的可能独特特征。