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Parker Solar Probe: Four Years of Discoveries at Solar Cycle Minimum
McComas, D. J.; Bale, S. D.; Matteini, L. +55 more
Launched on 12 Aug. 2018, NASA's Parker Solar Probe had completed 13 of its scheduled 24 orbits around the Sun by Nov. 2022. The mission's primary science goal is to determine the structure and dynamics of the Sun's coronal magnetic field, understand how the solar corona and wind are heated and accelerated, and determine what processes accelerate …
Extreme Solar Events: Setting up a Paradigm
Notsu, Yuta; Maehara, Hiroyuki; Dalla, Silvia +17 more
The Sun is magnetically active and often produces eruptive events on different energetic and temporal scales. Until recently, the upper limit of such events was unknown and believed to be roughly represented by direct instrumental observations. However, two types of extreme events were discovered recently: extreme solar energetic particle events o…
Future Exploration of the Outer Heliosphere and Very Local Interstellar Medium by Interstellar Probe
Wurz, P.; Krimigis, S. M.; Kurth, W. S. +40 more
A detailed overview of the knowledge gaps in our understanding of the heliospheric interaction with the largely unexplored Very Local Interstellar Medium (VLISM) are provided along with predictions of with the scientific discoveries that await. The new measurements required to make progress in this expanding frontier of space physics are discussed…
Investigating Europa's Radiation Environment with the Europa Clipper Radiation Monitor
McEwen, Alfred; Clark, Roger; Paranicas, Chris +23 more
We present an overview of the radiation environment monitoring program planned for the Europa Clipper mission. The harsh radiation environment of Jupiter will be measured by a dedicated Radiation Monitor (RadMon) subsystem, yielding mission accumulative Total Ionizing Dose (TID) and instantaneous electron flux measurements with a 1-Hz cadence. The…
Theory of Cosmic Ray Transport in the Heliosphere
Rankin, J. S.; Potgieter, M. S.; Ruffolo, D. +6 more
Modelling the transport of cosmic rays (CRs) in the heliosphere represents a global challenge in the field of heliophysics, in that such a study, if it were to be performed from first principles, requires the careful modelling of both large scale heliospheric plasma quantities (such as the global structure of the heliosphere, or the heliospheric m…
The Structure of the Large-Scale Heliosphere as Seen by Current Models
Heerikhuisen, Jacob; Fraternale, Federico; Pogorelov, Nikolai +6 more
This review summarizes the current state of research aiming at a description of the global heliosphere using both analytical and numerical modeling efforts, particularly in view of the overall plasma/neutral flow and magnetic field structure, and its relation to energetic neutral atoms. Being part of a larger volume on current heliospheric researc…
Anomalous Cosmic Rays and Heliospheric Energetic Particles
Fichtner, H.; Leske, R. A.; Hill, M. E. +7 more
We present a review of Anomalous Cosmic Rays (ACRs), including the history of their discovery and recent insights into their acceleration and transport in the heliosphere. We focus on a few selected topics including a discussion of mechanisms of their acceleration, escape from the heliosphere, their effects on the dynamics of the heliosheath, tran…
Recent Developments in Particle Acceleration at Shocks: Theory and Observations
Giacalone, Joe; Perri, Silvia; Fichtner, Horst +2 more
Energetic particles represent an important component of the plasma in the heliosphere. They range from particles accelerated at impulsive events in the solar corona and at large scale structures in the interplanetary medium, to anomalous cosmic rays accelerated at the boundaries of the heliosphere. In-situ satellite observations, numerical simulat…
Turbulence in the Outer Heliosphere
Zank, Gary P.; Adhikari, Laxman; Zhao, Lingling +9 more
The solar wind (SW) and local interstellar medium (LISM) are turbulent media. Their interaction is governed by complex physical processes and creates heliospheric regions with significantly different properties in terms of particle populations, bulk flow and turbulence. Our knowledge of the solar wind turbulence nature and dynamics mostly relies o…
In Situ Observations of Interstellar Pickup Ions from 1 au to the Outer Heliosphere
McComas, D. J.; Möbius, E.; Pogorelov, N. V. +5 more
Interstellar pickup ions are an ubiquitous and thermodynamically important component of the solar wind plasma in the heliosphere. These PUIs are born from the ionization of the interstellar neutral gas, consisting of hydrogen, helium, and trace amounts of heavier elements, in the solar wind as the heliosphere moves through the local interstellar m…