Journal article
Mars's magnetotail: Nature's current sheet laboratory
Journal of geophysical research. Space physics, Vol.122(5), pp.5404-5417
05/2017
DOI: 10.1002/2017JA024078
Abstract
The configuration and stability of an important kinetic plasma structure, the current sheet, determine the efficiency of magnetic energy storage, release, and transport in surrounding plasmas. These properties depend on β (the ratio of plasma pressures to magnetic field pressures) and Mach number M (the ratio of bulk velocities to magnetosonic velocities). For the most investigated current sheet, the near‐Earth magnetotail current sheet, these parameters fall within a relatively narrow range of values (high β, low M). To investigate current sheet behavior for a wider range of parameters, we explore current sheets in the magnetotail of Mars using Mars Atmosphere and Volatile Evolution (MAVEN) mission observations. We find that low‐β, high‐M current sheets are abundant in Mars's magnetotail, but high‐β, low‐M current sheets can also be found there. Low‐β current sheets are nearly force‐free, whereas high‐M current sheets are balanced by a plasma flow gradient along the tail. We compare current sheet distributions in a (β,M) space for the Martian magnetotail, the near‐Earth magnetotail (using Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission), and the distant magnetotail (using Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) mission). We also find that the pressure balance in the Martian magnetotail current sheet can occur by contributions from a wide range of ion species, or, in low beta cases, from field‐aligned currents generation of a force‐free magnetic field configuration. The Martian magnetotail is a natural laboratory where current sheet of various types can be found and investigated.
Key Points
Configuration and plasma parameters of Mars's magnetotail current sheets
Three types of current sheets with different pressure balances
Comparison of current sheet properties in Mars's and Earth's magnetotails
Details
- Title: Subtitle
- Mars's magnetotail: Nature's current sheet laboratory
- Creators
- A. V Artemyev - University of California, Los AngelesV Angelopoulos - University of California, Los AngelesJ. S Halekas - University of IowaA Runov - University of California, Los AngelesL. M Zelenyi - Space Research InstituteJ. P McFadden - University of California, Berkeley
- Resource Type
- Journal article
- Publication Details
- Journal of geophysical research. Space physics, Vol.122(5), pp.5404-5417
- DOI
- 10.1002/2017JA024078
- ISSN
- 2169-9380
- eISSN
- 2169-9402
- Number of pages
- 14
- Grant note
- NASA (NAS5-02099; NNX16AF84G) Russian Scientific Foundation (16-42-01103) German Aerospace Center (DLR) (50 OC 0302) German Ministry for Economy and Technology
- Language
- English
- Date published
- 05/2017
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984199678402771
Metrics
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