Living Reviews in Solar Physics: "Coronal mass ejections and their sheath regions in interplanetary space"

© SpringerKilpua, E., Koskinen, H.E.J. & Pulkkinen, T.I., "Coronal mass ejections and their sheath regions in interplanetary space", Living Rev Sol Phys (2017) 14: 5.

Open Access | Review Article

First Online: 24 November 2017


Interplanetary coronal mass ejections (ICMEs) are large-scale heliospheric transients that originate from the Sun. When an ICME is sufficiently faster than the preceding solar wind, a shock wave develops ahead of the ICME. The turbulent region between the shock and the ICME is called the sheath region. ICMEs and their sheaths and shocks are all interesting structures from the fundamental plasma physics viewpoint. They are also key drivers of space weather disturbances in the heliosphere and planetary environments. ICME-driven shock waves can accelerate charged particles to high energies. Sheaths and ICMEs drive practically all intense geospace storms at the Earth, and they can also affect dramatically the planetary radiation environments and atmospheres. This review focuses on the current understanding of observational signatures and properties of ICMEs and the associated sheath regions based on five decades of studies. In addition, we discuss modelling of ICMEs and many fundamental outstanding questions on their origin, evolution and effects, largely due to the limitations of single spacecraft observations of these macro-scale structures. We also present current understanding of space weather consequences of these large-scale solar wind structures, including effects at the other Solar System planets and exoplanets. We specially emphasize the different origin, properties and consequences of the sheaths and ICMEs.

The authors:

Emilia Kilpua is an Associate Professor at the Faculty of Science of the University of Helsinki. In December 2016, she was awarded with an ERC Consolidator Grant for her research on coronal mass ejections.

Hannu E. J. Koskinen is Professor in Space Physics at the Department of Physics of the University of Helsinki and the Finnish Meteorological Institute. He is author of the Springer-Praxis book "Physics of Space Storms: From the Solar Surface to the Earth".

Tuija I. Pulkkinen is Professor at the Department of Radio Science and Engineering, Aalto University, Espoo, Finland. In 2017, she received the Julius Bartels Medal of the EGU for her key contributions in solar-terrestrial science, scientific management, academic leadership, and services to the space community.