Induced Magnetic Fields and Plasma Motions in the Inner Part of the Martian Magnetosphere
Fraenz, M.
Modolo, R.
Pätzold, M.
Tellmann, S.
Vaisberg, O.
Shuvalov, S.
Zelenyi, L.
Chai, L.
Wei, Y.
McFadden, J.
DiBraccio, G.
Espley, J.
DOI: https://doi.org/10.1029/2021JA029542
Persistent URL: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/9759
Modolo, R.; 2 Rheinisches Institut Fuer Umweltforschung Cologne Germany
Pätzold, M.; 3 LATMOS/IPSL UVSQ Universite UPMC University Paris CNRS Guyancourt France
Tellmann, S.; 3 LATMOS/IPSL UVSQ Universite UPMC University Paris CNRS Guyancourt France
Vaisberg, O.; 4 Institute of Space Research Moscow Russia
Shuvalov, S.; 4 Institute of Space Research Moscow Russia
Zelenyi, L.; 4 Institute of Space Research Moscow Russia
Chai, L.; 5 Key Lab of Earth and Planetary Physics Institute of Geology and Geophysics Beijing People Republic of China
Wei, Y.; 5 Key Lab of Earth and Planetary Physics Institute of Geology and Geophysics Beijing People Republic of China
McFadden, J.; 6 Space Sciences Laboratory U. C. Berkeley Berkeley CA USA
DiBraccio, G.; 7 NASA Goddard Space Flight Center Greenbelt MD USA
Espley, J.; 7 NASA Goddard Space Flight Center Greenbelt MD USA
Abstract
Analysis of Mars Atmosphere and Volatile Evolution (MAVEN)/Supra‐Thermal And Thermal Ion Composition observations in the Martian upper atmosphere, bounded at higher altitudes by the shocked solar wind, shows that the draping of interplanetary magnetic field penetrates down to low altitudes (∼200−250 km) and governs dynamics of the ionosphere. The upper ionospheric plasma is driven into motion flowing around Mars similar to the shocked solar wind in the adjacent magnetosheath. Such a fluid‐like motion is accompanied by ion acceleration caused by the bending of the magnetic field, leading to ion extraction and finally to ion pickup. Extraction of ions and their acceleration produces a recoil effect of the bulk ionosphere in the opposite direction. This provides a strong asymmetry in ion dynamics in two different hemispheres, accompanied by wrapping of the magnetic field lines around Mars and respective reconnection.
Plain Language Summary: Although the Martian magnetosphere is hybrid and contains components of the induced and intrinsic magnetosphere, is possible to display these components by using the specific coordinate systems. Here we study the properties of the induced magnetosphere using the data obtained by MAVEN spacecraft. The interplanetary magnetic field penetrates deep into the Martian ionosphere draping around Mars and drive to the motion dense ionospheric plasma. Draping features and the induced plasma motions occur different in two hemispheres determined by the direction of the motional electric field in the solar wind. Ion acceleration and extraction is accompanied by a recoil effect that leads to a shift and asymmetry of the ionosphere.
Key Points:
Draping of the interplanetary magnetic field around Mars penetrates deep to the ionosphere enveloping the planet and driving the ionosphere to the bulk motion.
Draping and motion of the ionospheric plasma is characterized by asymmetry by the direction of the motional electric field in solar wind.
Ion acceleration and extraction from the ionosphere is accompanied by a shift of the bulk ionosphere in the opposite direction.