Voyager 1 has been moving through the very local interstellar medium (VLISM) from the time that it crossed the heliopause on 2012/DOY 238 to 2020/DOY 292. Three notable objects in the magnetic field of the VLISM have been observed: two shocks and one pressure front. This paper reports the observation of a fourth object observed near 2020/DOY 147. There were no upstream electron plasma oscillations of the type often observed ahead of shocks, abrupt increases in energetic particles, or fluctuations in the 48 s increments of the magnetic field associated with this feature, suggesting that it was probably not a shock. This feature was associated with a relatively large increase in the magnetic field strength (B2/B1 = 1.35) and in the electron density determined by the Plasma Wave Science experiment (N2/N1 = 1.36) using a new method described in this paper. This feature appears to be a pressure front associated with a compressive wave in the VLISM. The two shocks and the two pressure fronts were associated with the four largest maxima observed in B(t) between 2012/DOY 238 and 2020/DOY 292. Each feature was associated with a jump–ramp structure. The jump–ramp structures were separated by long relatively undisturbed quiet intervals.

从 2012/DOY 238 到 2020/DOY 292 穿越日光层顶，航海者 1 号一直在非常局域星际介质 (VLISM) 中移动。已观察到 VLISM 磁场中的三个显着物体：两次冲击和一压锋。本文报告了在 2020/DOY 147 附近观测到的第四个天体的观测结果。在冲击、高能粒子的突然增加或相关磁场的 48 s 增量波动之前，没有经常观测到的上游电子等离子体振荡。有了这个功能，暗示它可能不是一个震惊。该特征与磁场强度相对较大的增加有关 ( B 2/ B1 = 1.35) 和使用本文中描述的新方法通过等离子体波科学实验 ( N 2/ N 1 = 1.36)确定的电子密度。该特征似乎是与 VLISM 中的压缩波相关的压力前沿。两个冲击和两个压力前沿与2012/DOY 238 和 2020/DOY 292 之间在B ( t ) 中观察到的四个最大最大值相关。每个特征都与跳跃斜坡结构相关。跳跃斜坡结构被较长的相对不受干扰的安静间隔隔开。