Martian global current systems and related solar wind energy transfer: hybrid simulation under nominal conditionsShow others and affiliations
2024 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 527, no 4, p. 12232-12242Article in journal (Refereed) Published
Abstract [en]
The magnetized solar wind drives a current system around Mars that maintains its induced magnetosphere. The solar wind also transfers its energy to the atmospheric ions, causing continuous atmospheric erosion, which has a profound impact on the planet’s evolution history. Here, we use Amitis, a Graphics Processing Unit (GPU)-based hybrid plasma model to first reproduce the global pattern of the net electric current and ion currents under an interplanetary magnetic field perpendicular to the solar wind flow direction. The resultant current distribution matches the observations and reveals more details. Using the electric field distribution characterized earlier with the same model, we calculate for the first time the spatial distribution of energy transfer rate to the plasmas in general and to different ion species at Mars. We find out that (1) the solar wind kinetic energy is the dominant energy source that drives Martian induced magnetosphere, (2) the energy flux of the shocked solar wind flows from the magnetic equatorial plane towards the plasma sheet in the induced magnetotail, (3) both the bow shock and the induced magnetospheric boundary are dynamos where plasma energy is transferred to the electromagnetic field, and (4) the planetary ions act as loads and gain energy from the electromagnetic field. The most intense load region is the planetary ion plume. The general pattern of the energy transfer rate revealed in this study is common for induced magnetospheres. Its variabilities with the upstream conditions can provide physical insight into the observed ion escape variabilities.
Place, publisher, year, edition, pages
Oxford University Press, 2024. Vol. 527, no 4, p. 12232-12242
Keywords [en]
methods: numerical, planets and satellites: terrestrial planets, planet–star interactions, plasmas
National Category
Fusion, Plasma and Space Physics Astronomy, Astrophysics and Cosmology
Identifiers
URN: urn:nbn:se:umu:diva-220012DOI: 10.1093/mnras/stad3486ISI: 001142376400018Scopus ID: 2-s2.0-85182507230OAI: oai:DiVA.org:umu-220012DiVA, id: diva2:1832947
Funder
Swedish National Space Board, 127/14Swedish National Space Board, 115/18Swedish Research Council, 2018-03454Swedish National Infrastructure for Computing (SNIC), SNIC2020/5-101Swedish National Infrastructure for Computing (SNIC), SNIC2020/5-4592024-01-312024-01-312025-04-24Bibliographically approved