• Medientyp: E-Artikel
  • Titel: Magnetospheric quasi‐static response to the dynamic magnetosheath: A THEMIS case study
  • Beteiligte: Glassmeier, Karl‐Heinz; Auster, Hans‐Ulrich; Constantinescu, Dragoş; Fornaçon, Karl‐Heinz; Narita, Yasuhito; Plaschke, Ferdinand; Angelopoulos, Vassilis; Georgescu, Edita; Baumjohann, Wolfgang; Magnes, Werner; Nakamura, Rumi; Carlson, Charles W.; Frey, Sabine; McFadden, James P.; Phan, Tai; Mann, Ian; Rae, I. Jonathan; Vogt, Joachim
  • Erschienen: American Geophysical Union (AGU), 2008
  • Erschienen in: Geophysical Research Letters
  • Umfang:
  • Sprache: Englisch
  • DOI: 10.1029/2008gl033469
  • ISSN: 0094-8276; 1944-8007
  • Schlagwörter: General Earth and Planetary Sciences ; Geophysics
  • Zusammenfassung: <jats:p>Earth's magnetosphere is buffeted by the time‐varying solar wind. For the first time, the THEMIS mission, with its five spacecraft, directly allows to compare measurements in the magnetosheath and their response in the magnetopause boundary region, and the outer magnetosphere to this buffeting. During the time interval studied, the spacecraft moved almost along the stagnation streamline allowing to use Bernoulli's law to relate local observations of the plasma density, temperature, flow velocity, and magnetic field to the stagnation pressure. Magnetopause distance and velocity are determined assuming a quasi‐static response. The dynamics inferred is compared with actual observations by three of the THEMIS spacecraft. Assuming a radially moving Chapman‐Ferraro current layer also the outer magnetospheric magnetic field response is modelled and compared with magnetic field measurements. Most of the low‐frequency variability of the outer magnetosphere and magnetopause boundary can be understood as the result of a quasi‐static response of the magnetosphere to magnetosheath dynamic pressure variations.</jats:p>
  • Beschreibung: <jats:p>Earth's magnetosphere is buffeted by the time‐varying solar wind. For the first time, the THEMIS mission, with its five spacecraft, directly allows to compare measurements in the magnetosheath and their response in the magnetopause boundary region, and the outer magnetosphere to this buffeting. During the time interval studied, the spacecraft moved almost along the stagnation streamline allowing to use Bernoulli's law to relate local observations of the plasma density, temperature, flow velocity, and magnetic field to the stagnation pressure. Magnetopause distance and velocity are determined assuming a quasi‐static response. The dynamics inferred is compared with actual observations by three of the THEMIS spacecraft. Assuming a radially moving Chapman‐Ferraro current layer also the outer magnetospheric magnetic field response is modelled and compared with magnetic field measurements. Most of the low‐frequency variability of the outer magnetosphere and magnetopause boundary can be understood as the result of a quasi‐static response of the magnetosphere to magnetosheath dynamic pressure variations.</jats:p>
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  • Zugangsstatus: Freier Zugang