Burlaga L F, Ness N F, Acuña M H, Lepping R P, Connerney J E P, Richardson J D
NASA/Goddard Space Flight Center, Greenbelt, Maryland 20771, USA.
Nature. 2008 Jul 3;454(7200):75-7. doi: 10.1038/nature07029.
A transition between the supersonic solar wind and the subsonic heliosheath was observed by Voyager 1, but the expected termination shock was not seen owing to a gap in the telemetry. Here we report observations of the magnetic field structure and dynamics of the termination shock, made by Voyager 2 on 31 August-1 September 2007 at a distance of 83.7 au from the Sun (1 au is the Earth-Sun distance). A single crossing of the shock was expected, with a boundary that was stable on a timescale of several days. But the data reveal a complex, rippled, quasi-perpendicular supercritical magnetohydrodynamic shock of moderate strength undergoing reformation on a scale of a few hours. The observed structure suggests the importance of ionized interstellar atoms ('pickup protons') at the shock.
旅行者1号观测到了超音速太阳风与亚音速日球层顶之间的过渡，但由于遥测数据存在间隙，预期中的终端激波未被观测到。在此，我们报告旅行者2号于2007年8月31日至9月1日在距离太阳83.7天文单位（1天文单位为日地距离）处对终端激波的磁场结构和动力学进行的观测。预计会有一次对激波的单次穿越，其边界在数天的时间尺度上是稳定的。但数据显示，这是一个复杂的、有波纹的、中等强度的准垂直超临界磁流体动力学激波，正在以数小时的尺度进行重构。观测到的结构表明了激波处电离星际原子（“拾取质子”）的重要性。
