A Magnetohydrodynamic Simulation of the Interaction between the Solar Wind and Comet Halley

太阳风与哈雷彗星相互作用的磁流体动力学模拟

• 批准号: 61540306
• 负责人: OGINO Tatsuki
• 金额: $ 1.09万
• 依托单位: Research Institute of Atmospherics, Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61540306/
• 关键词: Comet Halley; Solar wind; Interaction; Magnetohydrodynamics; 計算機シミュレーション; シミュレーション

The interaction between the solar wind and the plasmas produced form cometary gases has been modeled by using a three-dimensional time-dependent magneto-hydrodynamic (MHD) simulation with the cometary mass loading. The model reproduced several features observed by the recent missions to comet Halley.A weak bow shock was located 3.2x10^5 km in front of the comet. The magnetic field increased by a factor of 3.7 across this weak bow shock and continued to increase up to the contact surface (B_<max>/B_<IMF>= 6-8). The plasma temperature increased across the bow shock and decreased nearer to the comet. Interplanetary magnetic field (IMF) lines were hung up on the comet and formed a long plasma tail in which the lobe field was quite strong and B_<lobe>/B_<IMF>-5. A cold dense plasma sheet formed in the tail and this thin plasma sheet was oriented normal the IMF direction.Ray-like structure and a plasmoid with high plasma pressure are formed in thecometary plasma tail and propagate tailward with a local Alfven speed, when the dynamic pressure of solar wind or the IMF changes. These results give an explanation on the dynamics of cometary tail which were shown by the observationsusing a lot of photos. Our global MHD simulation in the solar wind-comet interaction has made clear the role of cometary mass loading and also has given animportant incitement in comparison with the interaction between the solar wind and other planets.

太阳风与彗星气体产生的等离子体之间的相互作用已通过使用具有彗星质量载荷的三维时间相关磁流体动力学（MHD）模拟进行了建模。该模型再现了最近哈雷彗星任务中观察到的几个特征。弱弓形激波位于彗星前方 3.2x10^5 公里处。穿过该弱弓形激波，磁场增加了 3.7 倍，并继续增加直至接触表面 (B_<max>/B_<IMF>= 6-8)。穿过弓激波的等离子体温度升高，靠近彗星的等离子体温度降低。行星际磁场（IMF）线悬挂在彗星上，形成一条长长的等离子体尾，波瓣场很强，B_<lobe>/B_<IMF>-5。在尾部形成冷致密的等离子体片，该薄等离子体片的方向垂直于 IMF 方向。在彗星等离子体尾部形成射线状结构和具有高等离子体压力的等离子体团，并以局部阿尔文速度向尾部传播，当动态太阳风的压力或IMF的变化。这些结果解释了通过大量照片进行观测所显示的彗尾动力学。我们对太阳风与彗星相互作用的全球MHD模拟清楚了彗星质量载荷的作用，并且与太阳风与其他行星的相互作用相比也给出了重要的启发。

项目成果

T.Ogino: UCLA IGPP Publ. 3047 submitted to Journal of Geophysical Research. (1987)

T.Ogino：加州大学洛杉矶分校 IGPP 出版物。

T.Ogino: The International Plasma Workshop in Tokyo,ed.by H.Kikuchi,Springer. (1988)

T.Ogino：东京国际等离子体研讨会，H.Kikuchi 编辑，Springer。

T. Ogino: "Two dimensional MHD simulation of the interaction between the solar wind and cometary outflowing plasmas" ISAS Research Report. 15. 109-120 (1986)

T. Ogino：“太阳风与彗星流出等离子体之间相互作用的二维 MHD 模拟”ISAS 研究报告。

T. Ogino: "A three dimensional MHD simulation of the interaction of the solar wind with comet Halley" UCLA IGPP Publ. 3047 submitted to Journal of Geophysical Research. (1987)

T. Ogino：“太阳风与哈雷彗星相互作用的三维 MHD 模拟”加州大学洛杉矶分校 IGPP 出版物。

T.Ogino: Proceedings of Chapman Conference on Plasma Waves and Instabilities in Magnetospheres and at Comets,by conveners:H.Oya and B.T.Tsurutani,. 84-87 (1987)

T.Ogino：查普曼关于磁层和彗星中的等离子体波和不稳定性的会议记录，召集人：H.Oya 和 B.T.Tsurutani。