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The Physical Processes of CME/ICME Evolution
Vršnak, Bojan; Lugaz, Noé; Liu, Ying D. +4 more
As observed in Thomson-scattered white light, coronal mass ejections (CMEs) are manifest as large-scale expulsions of plasma magnetically driven from the corona in the most energetic eruptions from the Sun. It remains a tantalizing mystery as to how these erupting magnetic fields evolve to form the complex structures we observe in the solar wind a…
Origins of the Ambient Solar Wind: Implications for Space Weather
Cranmer, Steven R.; Riley, Pete; Gibson, Sarah E.
The Sun's outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind. We also discuss where the community stands in its abilit…
Coronal Magnetic Field Models
Riley, Pete; Wiegelmann, Thomas; Petrie, Gordon J. D.
Coronal magnetic field models use photospheric field measurements as boundary condition to model the solar corona. We review in this paper the most common model assumptions, starting from MHD-models, magnetohydrostatics, force-free and finally potential field models. Each model in this list is somewhat less complex than the previous one and makes …
Measurements of Photospheric and Chromospheric Magnetic Fields
Gosain, Sanjay; Lagg, Andreas; Lites, Bruce +2 more
The Sun is replete with magnetic fields, with sunspots, pores and plage regions being their most prominent representatives on the solar surface. But even far away from these active regions, magnetic fields are ubiquitous. To a large extent, their importance for the thermodynamics in the solar photosphere is determined by the total magnetic flux. W…
Particle Radiation Sources, Propagation and Interactions in Deep Space, at Earth, the Moon, Mars, and Beyond: Examples of Radiation Interactions and Effects
Downs, Cooper; Riley, Pete; Kozarev, Kamen +13 more
Particle radiation has significant effects for astronauts, satellites and planetary bodies throughout the Solar System. Acute space radiation hazards pose risks to human and robotic exploration. This radiation also naturally weathers the exposed surface regolith of the Moon, the two moons of Mars, and other airless bodies, and contributes to chemi…
The Life Cycle of Active Region Magnetic Fields
Cheung, M. C. M.; van Driel-Gesztelyi, L.; Martínez Pillet, V. +1 more
We present a contemporary view of how solar active region magnetic fields are understood to be generated, transported and dispersed. Empirical trends of active region properties that guide model development are discussed. Physical principles considered important for active region evolution are introduced and advances in modeling are reviewed.
Minimal Magnetic States of the Sun and the Solar Wind: Implications for the Origin of the Slow Solar Wind
von Steiger, R.; Cliver, E. W.
During the last decade it has been proposed that both the Sun and the solar wind have minimum magnetic states, lowest order levels of magnetism that underlie the 11-yr cycle as well as longer-term variability. Here we review the literature on basal magnetic states at the Sun and in the heliosphere and draw a connection between the two based on the…