Solar wind interaction with comet 67P: Impacts of corotating interaction regions
Solar wind interaction with comet 67P: Impacts of corotating interaction regions
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太阳风与彗星 67P 的相互作用：同转相互作用区域的影响
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
G. S. Wieser
中科院分区：
文献类型：
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作者：
N. Edberg;A. Eriksson;E. Odelstad;E. Vigren;D. Andrews;F. L. Johansson;J. Burch;C. Carr;E. Cupido;K. Glassmeier;R. Goldstein;J. Halekas;P. Henri;C. Koenders;K. Mandt;P. Mokashi;Z. Németh;H. Nilsson;R. Ramstad;I. Richter;G. S. Wieser
我们展示了罗塞塔等离子体联盟对暴风雨太阳风对 67P/Churyumov-Gerasimenko 彗星影响的观测结果。从 2014 年 10 月到 12 月，从地球经火星（使用火星快车和火星大气和挥发性演化任务）追踪到 67P 号彗星的四个共转相互作用区域（CIR），其中第一个事件可能与日冕物质抛射合并。当彗星距太阳 3.1–2.7 个天文单位且中性逸气速率约为 1025–1026 s−1 时， CIR 显着影响 高度低至 10-30 公里的彗星等离子体环境。电离层低能（∼5 eV）等离子体密度在所有事件中均显着增加，事件 1 和 2 中的因子 >2，但事件 3 和 4 中的因子较小。当电子通量增加时，航天器电势在撞击时降至 -20 V 以下。密度的增加可能是由于等离子体环境的压缩、粒子碰撞电离的增加以及可能的电荷交换过程和负载质量的等离子体返回彗星电离层的加速造成的。在所有事件中，超热（∼10-100 eV）电子的通量显着增加，表明这些电子的加热机制与太阳风能输入耦合。撞击时，彗发中的磁场强度会增加 2-5 倍，因为彗星周围会堆积更多的行星际磁场。在两次 CIR 撞击事件中，我们观察到，随着强烈的太阳风压缩彗星等离子体环境，等离子体边界可能形成或移动经过罗塞塔。我们还讨论了看到电离层对尾部断开事件响应的一些特征的可能性。
We present observations from the Rosetta Plasma Consortium of the effects of stormy solar wind on comet 67P/Churyumov‐Gerasimenko. Four corotating interaction regions (CIRs), where the first event has possibly merged with a coronal mass ejection, are traced from Earth via Mars (using Mars Express and Mars Atmosphere and Volatile EvolutioN mission) to comet 67P from October to December 2014. When the comet is 3.1–2.7 AU from the Sun and the neutral outgassing rate ∼1025–1026 s−1, the CIRs significantly influence the cometary plasma environment at altitudes down to 10–30 km. The ionospheric low‐energy (∼5 eV) plasma density increases significantly in all events, by a factor of >2 in events 1 and 2 but less in events 3 and 4. The spacecraft potential drops below −20 V upon impact when the flux of electrons increases. The increased density is likely caused by compression of the plasma environment, increased particle impact ionization, and possibly charge exchange processes and acceleration of mass‐loaded plasma back to the comet ionosphere. During all events, the fluxes of suprathermal (∼10–100 eV) electrons increase significantly, suggesting that the heating mechanism of these electrons is coupled to the solar wind energy input. At impact the magnetic field strength in the coma increases by a factor of 2–5 as more interplanetary magnetic field piles up around the comet. During two CIR impact events, we observe possible plasma boundaries forming, or moving past Rosetta, as the strong solar wind compresses the cometary plasma environment. We also discuss the possibility of seeing some signatures of the ionospheric response to tail disconnection events.
影响因子：
5.2
作者：
N. Edberg;Hans Nilsson;A. O. Williams;Mark Lester;S. Milan;S. Cowley;M. Fränz;S. Barabash;Y. Futaana
通讯作者：
N. Edberg;Hans Nilsson;A. O. Williams;Mark Lester;S. Milan;S. Cowley;M. Fränz;S. Barabash;Y. Futaana