Review and comparison of MHD wave characteristics at the Sun and in Earth’s magnetosphere

Abstract

Magnetohydrodynamic (MHD) waves play a crucial role in the plasma processes of stellar atmospheres and planetary magnetospheres. Wave phenomena in both media are known to have similarities and unique traits typical of each system.
 MHD waves and related phenomena in magnetospheric and solar physics are studied largely independently of each other, despite the similarity in properties of these media and the common physical foundations of wave generation and propagation. A unified approach to studying MHD waves in the Sun and Earth's magnetosphere opens up prospects for further progress in these two fields.
 The review examines the current state of research into MHD waves in the Sun’s atmosphere and Earth's magnetosphere. It outlines the main features of the wave propagation media: their structure, scales, and typical parameters. We describe the main theoretical models applied to wave behavior studies; discuss their advantages and limitations; compare characteristics of MHD waves in the Sun’s atmosphere and Earth’s magnetosphere; and review observation methods and tools to obtain information on waves in various media.

Plasmasphere Control of ULF Wave Distribution at Different Geomagnetic Conditions

“…Earth's magnetosphere is a natural shield on a way of solar particles, protecting technological systems and human health (Baker, 1996; Pilipenko, 2021). Large scale energy transport is carried out by magnetohydrodynamic (MHD) waves in both solar atmosphere and terrestrial magnetosphere (Chelpanov et al., 2022; Nakariakov et al., 2016). In the magnetosphere, MHD waves fall into the ultra‐low frequency (ULF) band and usually have frequency within Pc4 (6.7–22 mHz) and Pc5 (1.7–6.7 mHz) ranges (Jacobs et al., 1964; Troitskaya & Gul'elmi, 1967).…”

Observational signature of continuously operating drivers of decayless kink oscillation

“…Kink-mode oscillations are usually identified as transverse oscillations of loop-like structures and they are always characterized by non-axisymmetric and weakly compressive in the long-wavelength regime (see Nakariakov et al 2021, for a recent review). Kink oscillations are well studied magnetohydrodynamic (MHD) waves, since they play a crucial role in diagnosing the solar magnetic field and measuring plasma parameters, namely, "MHD coronal seismology" (e.g., Yuan & Van Doorsselaere 2016;Yang et al 2020;Chelpanov et al 2022). They are generally manifested as one of two forms: decaying and decayless oscillations, which are usually dependent on their oscillation amplitudes.…”