Has the Sun Significantly Impacted Recent Voyager Observations?
Abstract
Using our models HAFSS (HAF Source Surface) and HHMS-PI (Hybrid Heliospheric Modeling System with Pickup Protons) we have been analyzing some of the recent (e.g., July 2012, etc.) solar events to determine if the effects of the events might be seen in the outer heliosphere, heliosheath, etc. Our analyses provide insights into the phenomena in these regions. Both models are three-dimensional (3D) time dependent simulations that use solar observations as input. HAFSS is a kinematic model. HHMS-PI is a numerical magnetohydrodynamic solar wind (SW) simulation model. Both HHMS-PI and HAFSS are ideally suited for these analyses since starting from the Sun they model the slowly evolving background SW and the impulsive, time-dependent events associated with solar activity (e.g., coronal mass ejections (CMEs). HHMS-PI/HAFSS make it possible to track interplanetary shocks as they propagate, interact, and evolve en route to various spacecraft (s/c) where they are observed. Our models have been used to reproduce s/c data from ACE to Ulysses, Cassini, and Voyagers 1 and 2. Our published results in refereed scientific journals showed that: a.) Our models naturally reproduce dynamic 3D spatially asymmetric effects observed throughout the heliosphere. b.) Pre-existing SW background conditions have a strong influence on the propagation of shock waves from solar events. c.) Time-dependence is a crucial aspect of interpreting s/c data. d.) Shock interactions resulting from multiple solar events lead to complicated time-series observations at individual s/c. We believe the answer to the question in the title of this abstract is: Yes, we do think the Sun has significantly impacted recent Voyager observations.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFMSH11B1975I
- Keywords:
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- 2126 INTERPLANETARY PHYSICS Heliosphere/interstellar medium interactions;
- 7514 SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY Energetic particles;
- 2124 INTERPLANETARY PHYSICS Heliopause and solar wind termination;
- 2104 INTERPLANETARY PHYSICS Cosmic rays