Heliosphere Configuration Insights from the Voyagers’ Heliopause Crossings and Solar Disturbance Propagations

Abstract

Abstract The Voyager 1 and 2 (V1 and V2) crossings of the heliopause (HP) have generated new estimates of the shape of the heliosphere, helped elucidate plasma wave features, and helped clarify particle and field phenomena, all of which provide insights into the overall configuration of the heliosphere and its interaction with the local interstellar medium (LISM). Webber and Intriligator (2011) suggested a consistent offset in the V1 and V2 locations of the termination shock (TS), predicted a shrunken and squashed geometry of the heliosphere, and correctly predicted that V1 would encounter the HP in 2012.0 ± 1 year. Intriligator et al. (2005, 2008) examined how the Halloween 2003 solar events were manifested from the Sun to V1 and V2 at 92.6 and 73.2 AU, giving rise to Global Merged Interaction Regions (GMIRs) and to broad particle, plasma, and magnetic field offsets that could affect the configuration of the heliosphere. The 2012 solar events (Intriligator et al., 2015) appeared to cause a tsunami at V1 and V2 at 128.7 and 102.5 AU and emphasized that space weather often could be interpreted as TS or HP or heliospheric crossings. Washimi et al. (2017) suggested that further complications of these events could propagate from the LISM back into the heliosphere. We conclude that in addition to the LISM magnetic field, the size and shape of the heliosphere are affected on differing time and space scales by changes in the average solar wind dynamic pressure over solar cycles with changing configurations of coronal holes, by pressure increases from GMIRs, and by magnetohydrodynamic instabilities that may be enhanced by energetic neutral atoms formed in GMIRs. We suggest the value of additional simulations that would combine our use of source surface maps of solar activity with other computational refinements.