在太阳活动极小期，很少或几乎没有太阳风进入金星大气层。

Little or no solar wind enters Venus' atmosphere at solar minimum.

作者信息

Zhang T L, Delva M, Baumjohann W, Auster H-U, Carr C, Russell C T, Barabash S, Balikhin M, Kudela K, Berghofer G, Biernat H K, Lammer H, Lichtenegger H, Magnes W, Nakamura R, Schwingenschuh K, Volwerk M, Vörös Z, Zambelli W, Fornacon K-H, Glassmeier K-H, Richter I, Balogh A, Schwarzl H, Pope S A, Shi J K, Wang C, Motschmann U, Lebreton J-P

机构信息

Space Research Institute, Austrian Academy of Sciences, A-8042 Graz, Austria.

出版信息

Nature. 2007 Nov 29;450(7170):654-6. doi: 10.1038/nature06026.

DOI:10.1038/nature06026

PMID:18046399

Abstract

Venus has no significant internal magnetic field, which allows the solar wind to interact directly with its atmosphere. A field is induced in this interaction, which partially shields the atmosphere, but we have no knowledge of how effective that shield is at solar minimum. (Our current knowledge of the solar wind interaction with Venus is derived from measurements at solar maximum.) The bow shock is close to the planet, meaning that it is possible that some solar wind could be absorbed by the atmosphere and contribute to the evolution of the atmosphere. Here we report magnetic field measurements from the Venus Express spacecraft in the plasma environment surrounding Venus. The bow shock under low solar activity conditions seems to be in the position that would be expected from a complete deflection by a magnetized ionosphere. Therefore little solar wind enters the Venus ionosphere even at solar minimum.

摘要

金星没有显著的内部磁场，这使得太阳风能够直接与它的大气层相互作用。在这种相互作用中会感应出一个磁场，该磁场会部分地保护大气层，但我们并不清楚在太阳活动极小期时这种保护的效果如何。（我们目前对太阳风与金星相互作用的了解来自于太阳活动极大期的测量数据。）弓形激波距离金星很近，这意味着有可能一些太阳风会被大气层吸收，并对大气层的演化产生影响。在此，我们报告来自金星快车号航天器在金星周围等离子体环境中的磁场测量结果。低太阳活动条件下的弓形激波似乎处于由磁化电离层完全偏转所预期的位置。因此，即使在太阳活动极小期，进入金星电离层的太阳风也很少。