Electromotive field in space and astrophysical plasmas

TL;DR

This paper reviews the concept of electromotive fields in space and astrophysical plasmas, emphasizing their role in turbulence, theoretical understanding, and observations across various cosmic environments.

Contribution

It provides a comprehensive overview of electromotive fields, integrating theoretical insights with spacecraft observations and applications in diverse astrophysical contexts.

Findings

Electromotive fields are crucial for closing magnetohydrodynamic equations.

Observations support the theoretical role of electromotive fields in plasma turbulence.

Applications extend to Earth's magnetosphere, shocks, interstellar medium, and jets.

Abstract

The concept of electromotive field appears in various applications in space and astrophysical plasmas. A review is given on the electromotive field highlighting our current understanding of the theoretical picture and the spacecraft observations in interplanetary space. The electromotive field is a key concept to successfully close the set of turbulent magnetohydrodynamic equations and also to construct a more complete picture of space plasma turbulence. Applications to astrophysical cases (Earth magnetosphere, heliospheric shocks, interstellar medium, and relativistic jets) are also briefly introduced, as well.