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Brandt PC, Provornikova E, Bale SD, Cocoros A, DeMajistre R, Dialynas K, Elliott HA, Eriksson S, Fields B, Galli A, Hill ME, Horanyi M, Horbury T, Hunziker S, Kollmann P, Kinnison J, Fountain G, Krimigis SM, Kurth WS, Linsky J, Lisse CM, Mandt KE, Magnes W, McNutt RL, Miller J, Moebius E, Mostafavi P, Opher M, Paxton L, Plaschke F, Poppe AR, Roelof EC, Runyon K, Redfield S, Schwadron N, Sterken V, Swaczyna P, Szalay J, Turner D, Vannier H, Wimmer-Schweingruber R, Wurz P, Zirnstein EJ. Future Exploration of the Outer Heliosphere and Very Local Interstellar Medium by Interstellar Probe. Space Sci Rev 2023; 219:18. [PMID: 36874191 PMCID: PMC9974711 DOI: 10.1007/s11214-022-00943-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 12/07/2022] [Indexed: 06/18/2023]
Abstract
A detailed overview of the knowledge gaps in our understanding of the heliospheric interaction with the largely unexplored Very Local Interstellar Medium (VLISM) are provided along with predictions of with the scientific discoveries that await. The new measurements required to make progress in this expanding frontier of space physics are discussed and include in-situ plasma and pick-up ion measurements throughout the heliosheath, direct sampling of the VLISM properties such as elemental and isotopic composition, densities, flows, and temperatures of neutral gas, dust and plasma, and remote energetic neutral atom (ENA) and Lyman-alpha (LYA) imaging from vantage points that can uniquely discern the heliospheric shape and bring new information on the interaction with interstellar hydrogen. The implementation of a pragmatic Interstellar Probe mission with a nominal design life to reach 375 Astronomical Units (au) with likely operation out to 550 au are reported as a result of a 4-year NASA funded mission study.
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Affiliation(s)
- P. C. Brandt
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - E. Provornikova
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - S. D. Bale
- University of California Berkeley, Berkeley, CA USA
| | - A. Cocoros
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - R. DeMajistre
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - K. Dialynas
- Office of Space Research and Technology, Academy of Athens, Athens, 10679 Greece
| | | | - S. Eriksson
- Laboratory for Atmospheric and Space Physics, University of Colorado at Boulder, Boulder, CO USA
| | - B. Fields
- University of Illinois Urbana-Champaign, Urbana, IL USA
| | - A. Galli
- University of Bern, Bern, Switzerland
| | - M. E. Hill
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - M. Horanyi
- Laboratory for Atmospheric and Space Physics, University of Colorado at Boulder, Boulder, CO USA
| | | | | | - P. Kollmann
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - J. Kinnison
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - G. Fountain
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - S. M. Krimigis
- Office of Space Research and Technology, Academy of Athens, Athens, 10679 Greece
| | | | - J. Linsky
- University of Colorado Boulder, Boulder, CO USA
| | - C. M. Lisse
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - K. E. Mandt
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - W. Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - R. L. McNutt
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | | | - E. Moebius
- University of New Hampshire, Durham, NH USA
| | - P. Mostafavi
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - M. Opher
- Boston University, Boston, MA USA
| | - L. Paxton
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - F. Plaschke
- Technical University Braunschweig, Braunschweig, Germany
| | - A. R. Poppe
- University of California Berkeley, Berkeley, CA USA
| | - E. C. Roelof
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - K. Runyon
- Planetary Science Institute, Tucson, AZ USA
| | | | | | | | | | - J. Szalay
- Princeton University, Princeton, NJ USA
| | - D. Turner
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | | | | | - P. Wurz
- University of Bern, Bern, Switzerland
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Archer MO, Hartinger MD, Plaschke F, Southwood DJ, Rastaetter L. Magnetopause ripples going against the flow form azimuthally stationary surface waves. Nat Commun 2021; 12:5697. [PMID: 34615864 PMCID: PMC8494893 DOI: 10.1038/s41467-021-25923-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 08/30/2021] [Indexed: 11/27/2022] Open
Abstract
Surface waves process the turbulent disturbances which drive dynamics in many space, astrophysical and laboratory plasma systems, with the outer boundary of Earth’s magnetosphere, the magnetopause, providing an accessible environment to study them. Like waves on water, magnetopause surface waves are thought to travel in the direction of the driving solar wind, hence a paradigm in global magnetospheric dynamics of tailward propagation has been well-established. Here we show through multi-spacecraft observations, global simulations, and analytic theory that the lowest-frequency impulsively-excited magnetopause surface waves, with standing structure along the terrestrial magnetic field, propagate against the flow outside the boundary. Across a wide local time range (09–15h) the waves’ Poynting flux exactly balances the flow’s advective effect, leading to no net energy flux and thus stationary structure across the field also. Further down the equatorial flanks, however, advection dominates hence the waves travel downtail, seeding fluctuations at the resonant frequency which subsequently grow in amplitude via the Kelvin-Helmholtz instability and couple to magnetospheric body waves. This global response, contrary to the accepted paradigm, has implications on radiation belt, ionospheric, and auroral dynamics and potential applications to other dynamical systems. The magnetopause surface waves (SW) that drive global plasma dynamics are thought, like waves on water, to travel with the driving solar wind. Here, the authors show that impulsively-excited SW, with standing structure along the geomagnetic field, are stationary by propagating against this flow.
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Affiliation(s)
- M O Archer
- Space and Atmospheric Physics Group, Department of Physics, Imperial College London, London, UK.
| | | | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - D J Southwood
- Space and Atmospheric Physics Group, Department of Physics, Imperial College London, London, UK
| | - L Rastaetter
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
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3
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Nakamura TKM, Plaschke F, Hasegawa H, Liu Y, Hwang K, Blasl KA, Nakamura R. Decay of Kelvin-Helmholtz Vortices at the Earth's Magnetopause Under Pure Southward IMF Conditions. Geophys Res Lett 2020; 47:e2020GL087574. [PMID: 32999512 PMCID: PMC7507125 DOI: 10.1029/2020gl087574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/20/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
At the Earth's low-latitude magnetopause, clear signatures of the Kelvin-Helmholtz (KH) waves have been frequently observed during periods of the northward interplanetary magnetic field (IMF), whereas these signatures have been much less frequently observed during the southward IMF. Here, we performed the first 3-D fully kinetic simulation of the magnetopause KH instability under the southward IMF condition. The simulation demonstrates that fast magnetic reconnection is induced at multiple locations along the vortex edge in an early nonlinear growth phase of the instability. The reconnection outflow jets significantly disrupt the flow of the nonlinear KH vortex, while the disrupted turbulent flow strongly bends and twists the reconnected field lines. The resulting coupling of the complex field and flow patterns within the magnetopause boundary layer leads to a quick decay of the vortex structure, which may explain the difference in the observation probability of KH waves between northward and southward IMF conditions.
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Affiliation(s)
| | - F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | - Y.‐H. Liu
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - K. A. Blasl
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of PhysicsUniversity of GrazGrazAustria
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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4
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Archer MO, Hietala H, Hartinger MD, Plaschke F, Angelopoulos V. Direct observations of a surface eigenmode of the dayside magnetopause. Nat Commun 2019; 10:615. [PMID: 30755606 PMCID: PMC6372605 DOI: 10.1038/s41467-018-08134-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 12/11/2018] [Indexed: 11/26/2022] Open
Abstract
The abrupt boundary between a magnetosphere and the surrounding plasma, the magnetopause, has long been known to support surface waves. It was proposed that impulses acting on the boundary might lead to a trapping of these waves on the dayside by the ionosphere, resulting in a standing wave or eigenmode of the magnetopause surface. No direct observational evidence of this has been found to date and searches for indirect evidence have proved inconclusive, leading to speculation that this mechanism might not occur. By using fortuitous multipoint spacecraft observations during a rare isolated fast plasma jet impinging on the boundary, here we show that the resulting magnetopause motion and magnetospheric ultra-low frequency waves at well-defined frequencies are in agreement with and can only be explained by the magnetopause surface eigenmode. We therefore show through direct observations that this mechanism, which should impact upon the magnetospheric system globally, does in fact occur. Surface waves on the boundary between a magnetosphere and the surrounding plasma might get trapped by the ionosphere forming an eigenmode. Here, Archer et al. show direct observations of this proposed mechanism at Earth’s magnetosphere by analyzing the response to an isolated fast plasma jet detected by the THEMIS satellites.
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Affiliation(s)
- M O Archer
- School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London, E1 4NS, UK. .,Space and Atmospheric Physics Group, Department of Physics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
| | - H Hietala
- Department of Earth, Planetary and Space Sciences, University of California, Los Angeles, 595 Charles Young Drive East CA, 90095-1567, USA.,Space Research Laboratory, Department of Physics and Astronomy, University of Turku, 20500, Turku, Finland
| | - M D Hartinger
- Space Science Institute, 4750 Walnut St Suite 205, Boulder, CO, 80301, USA.,Department of Electrical and Computer Engineering, Virginia Tech, Perry St, Blacksburg, VA, 24060, USA
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstraße 6, 8042, Graz, Austria
| | - V Angelopoulos
- Department of Earth, Planetary and Space Sciences, University of California, Los Angeles, 595 Charles Young Drive East CA, 90095-1567, USA
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5
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Angelopoulos V, Cruce P, Drozdov A, Grimes EW, Hatzigeorgiu N, King DA, Larson D, Lewis JW, McTiernan JM, Roberts DA, Russell CL, Hori T, Kasahara Y, Kumamoto A, Matsuoka A, Miyashita Y, Miyoshi Y, Shinohara I, Teramoto M, Faden JB, Halford AJ, McCarthy M, Millan RM, Sample JG, Smith DM, Woodger LA, Masson A, Narock AA, Asamura K, Chang TF, Chiang CY, Kazama Y, Keika K, Matsuda S, Segawa T, Seki K, Shoji M, Tam SWY, Umemura N, Wang BJ, Wang SY, Redmon R, Rodriguez JV, Singer HJ, Vandegriff J, Abe S, Nose M, Shinbori A, Tanaka YM, UeNo S, Andersson L, Dunn P, Fowler C, Halekas JS, Hara T, Harada Y, Lee CO, Lillis R, Mitchell DL, Argall MR, Bromund K, Burch JL, Cohen IJ, Galloy M, Giles B, Jaynes AN, Le Contel O, Oka M, Phan TD, Walsh BM, Westlake J, Wilder FD, Bale SD, Livi R, Pulupa M, Whittlesey P, DeWolfe A, Harter B, Lucas E, Auster U, Bonnell JW, Cully CM, Donovan E, Ergun RE, Frey HU, Jackel B, Keiling A, Korth H, McFadden JP, Nishimura Y, Plaschke F, Robert P, Turner DL, Weygand JM, Candey RM, Johnson RC, Kovalick T, Liu MH, McGuire RE, Breneman A, Kersten K, Schroeder P. The Space Physics Environment Data Analysis System (SPEDAS). Space Sci Rev 2019; 215:9. [PMID: 30880847 PMCID: PMC6380193 DOI: 10.1007/s11214-018-0576-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 12/29/2018] [Indexed: 05/31/2023]
Abstract
With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- V. Angelopoulos
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - P. Cruce
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - A. Drozdov
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - E. W. Grimes
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - N. Hatzigeorgiu
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - D. A. King
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - D. Larson
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - J. W. Lewis
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - J. M. McTiernan
- Space Sciences Laboratory, University of California, Berkeley, USA
| | | | - C. L. Russell
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - T. Hori
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | | | - A. Kumamoto
- Tohoku University, 6-3, Aoba, Aramaki, Aoba Sendai, 980-8578 Japan
| | - A. Matsuoka
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - Y. Miyashita
- Korea Astronomy and Space Science Institute, Daejeon, South Korea
| | - Y. Miyoshi
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - I. Shinohara
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - M. Teramoto
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | | | - A. J. Halford
- Space Sciences Department, The Aerospace Corporation, Chantilly, VA USA
| | - M. McCarthy
- Department of Earth and Space Sciences, University of Washington, Seattle, WA USA
| | - R. M. Millan
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH USA
| | - J. G. Sample
- Department of Physics, Montana State University, Bozeman, MT USA
| | - D. M. Smith
- Santa Cruz Institute of Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 USA
| | - L. A. Woodger
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH USA
| | - A. Masson
- European Space Agency, ESAC, SCI-OPD, Madrid, Spain
| | - A. A. Narock
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - K. Asamura
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - T. F. Chang
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - C.-Y. Chiang
- Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Y. Kazama
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan
| | - K. Keika
- Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - S. Matsuda
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - T. Segawa
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - K. Seki
- Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - M. Shoji
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - S. W. Y. Tam
- Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan, Taiwan
| | - N. Umemura
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - B.-J. Wang
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan
- Graduate Institute of Space Science, National Central University, Taoyuan, Taiwan
| | - S.-Y. Wang
- Academia Sinica Institute of Astronomy and Astrophysics, Taipei, Taiwan
| | - R. Redmon
- National Centers for Environmental Information, National Oceanic and Atmospheric Administration, Boulder, CO USA
| | - J. V. Rodriguez
- National Centers for Environmental Information, National Oceanic and Atmospheric Administration, Boulder, CO USA
- Cooperative Institute for Research in Environmental Sciences (CIRES) at University of Colorado at Boulder, Boulder, CO USA
| | - H. J. Singer
- Space Weather Prediction Center, National Oceanic and Atmospheric Administration, Boulder, CO USA
| | - J. Vandegriff
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - S. Abe
- International Center for Space Weather Science and Education, Kyushu University, Fukuoka, Japan
| | - M. Nose
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
- World Data Center for Geomagnetism, Kyoto Data Analysis Center for Geomagnetism and Space Magnetism, Kyoto University, Kyoto, Japan
| | - A. Shinbori
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - Y.-M. Tanaka
- National Institute of Polar Research, Tokyo, Japan
| | - S. UeNo
- Hida Observatory, Kyoto University, Kyoto, Japan
| | - L. Andersson
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - P. Dunn
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - C. Fowler
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - J. S. Halekas
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA USA
| | - T. Hara
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - Y. Harada
- Department of Geophysics, Kyoto University, Kyoto, Japan
| | - C. O. Lee
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - R. Lillis
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - D. L. Mitchell
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - M. R. Argall
- Physics Department and Space Science Center, University of New Hampshire, Durham, NH USA
| | - K. Bromund
- NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - J. L. Burch
- Southwest Research Institute, San Antonio, TX USA
| | - I. J. Cohen
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - M. Galloy
- National Center for Atmospheric Research, Boulder, CO USA
| | - B. Giles
- NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - A. N. Jaynes
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA USA
| | - O. Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | - M. Oka
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - T. D. Phan
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - B. M. Walsh
- Center for Space Physics, Department of Mechanical Engineering, Boston University, Boston, MA USA
| | - J. Westlake
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - F. D. Wilder
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - S. D. Bale
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - R. Livi
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - M. Pulupa
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - P. Whittlesey
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - A. DeWolfe
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - B. Harter
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - E. Lucas
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - U. Auster
- Institute for Geophysics and Extraterrestrial Physics, Technical University of Braunschweig, Braunschweig, Germany
| | - J. W. Bonnell
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - C. M. Cully
- University of Calgary, Calgary, Ontario Canada
| | - E. Donovan
- University of Calgary, Calgary, Ontario Canada
| | - R. E. Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - H. U. Frey
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - B. Jackel
- University of Calgary, Calgary, Ontario Canada
| | - A. Keiling
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - H. Korth
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - J. P. McFadden
- Space Sciences Laboratory, University of California, Berkeley, USA
| | - Y. Nishimura
- Center for Space Physics and Department of Electrical and Computer Engineering, Boston University, Boston, MA USA
| | - F. Plaschke
- Space Research Institute, Austrian Academy of Sciences, Institute of Physics, University of Graz, Graz, Austria
| | - P. Robert
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | | | - J. M. Weygand
- Department of Earth, Planetary and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, USA
| | - R. M. Candey
- NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - R. C. Johnson
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - T. Kovalick
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | - M. H. Liu
- ADNET Systems Inc., NASA Goddard Space Flight Center, Greenbelt, MD USA
| | | | - A. Breneman
- University of Minnesota, Minneapolis, MN USA
| | - K. Kersten
- University of Minnesota, Minneapolis, MN USA
| | - P. Schroeder
- Space Sciences Laboratory, University of California, Berkeley, USA
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6
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Genestreti KJ, Nakamura TKM, Nakamura R, Denton RE, Torbert RB, Burch JL, Plaschke F, Fuselier SA, Ergun RE, Giles BL, Russell CT. How Accurately Can We Measure the Reconnection Rate E M for the MMS Diffusion Region Event of 11 July 2017? J Geophys Res Space Phys 2018; 123:9130-9149. [PMID: 30775197 PMCID: PMC6360497 DOI: 10.1029/2018ja025711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/10/2018] [Accepted: 09/11/2018] [Indexed: 06/09/2023]
Abstract
We investigate the accuracy with which the reconnection electric field E M can be determined from in situ plasma data. We study the magnetotail electron diffusion region observed by National Aeronautics and Space Administration's Magnetospheric Multiscale (MMS) on 11 July 2017 at 22:34 UT and focus on the very large errors in E M that result from errors in an L M N boundary normal coordinate system. We determine several L M N coordinates for this MMS event using several different methods. We use these M axes to estimate E M. We find some consensus that the reconnection rate was roughly E M = 3.2 ± 0.6 mV/m, which corresponds to a normalized reconnection rate of 0.18 ± 0.035. Minimum variance analysis of the electron velocity (MVA-v e), MVA of E, minimization of Faraday residue, and an adjusted version of the maximum directional derivative of the magnetic field (MDD-B) technique all produce reasonably similar coordinate axes. We use virtual MMS data from a particle-in-cell simulation of this event to estimate the errors in the coordinate axes and reconnection rate associated with MVA-v e and MDD-B. The L and M directions are most reliably determined by MVA-v e when the spacecraft observes a clear electron jet reversal. When the magnetic field data have errors as small as 0.5% of the background field strength, the M direction obtained by MDD-B technique may be off by as much as 35°. The normal direction is most accurately obtained by MDD-B. Overall, we find that these techniques were able to identify E M from the virtual data within error bars ≥20%.
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Affiliation(s)
- K. J. Genestreti
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Now at Space Science CenterUniversity of New HampshireDurhamNHUSA
| | | | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
| | - F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - S. A. Fuselier
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - R. E. Ergun
- Laboratory of Atmospheric and Space SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - B. L. Giles
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
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7
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Varsani A, Nakamura R, Sergeev VA, Baumjohann W, Owen CJ, Petrukovich AA, Yao Z, Nakamura TKM, Kubyshkina MV, Sotirelis T, Burch JL, Genestreti KJ, Vörös Z, Andriopoulou M, Gershman DJ, Avanov LA, Magnes W, Russell CT, Plaschke F, Khotyaintsev YV, Giles BL, Coffey VN, Dorelli JC, Strangeway RJ, Torbert RB, Lindqvist P, Ergun R. Simultaneous Remote Observations of Intense Reconnection Effects by DMSP and MMS Spacecraft During a Storm Time Substorm. J Geophys Res Space Phys 2017; 122:10891-10909. [PMID: 29399431 PMCID: PMC5784414 DOI: 10.1002/2017ja024547] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/27/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
During a magnetic storm on 23 June 2015, several very intense substorms took place, with signatures observed by multiple spacecraft including DMSP and Magnetospheric Multiscale (MMS). At the time of interest, DMSP F18 crossed inbound through a poleward expanding auroral bulge boundary at 23.5 h magnetic local time (MLT), while MMS was located duskward of 22 h MLT during an inward crossing of the expanding plasma sheet boundary. The two spacecraft observed a consistent set of signatures as they simultaneously crossed the reconnection separatrix layer during this very intense reconnection event. These include (1) energy dispersion of the energetic ions and electrons traveling earthward, accompanied with high electron energies in the vicinity of the separatrix; (2) energy dispersion of polar rain electrons, with a high-energy cutoff; and (3) intense inward convection of the magnetic field lines at the MMS location. The high temporal resolution measurements by MMS provide unprecedented observations of the outermost electron boundary layer. We discuss the relevance of the energy dispersion of the electrons, and their pitch angle distribution, to the spatial and temporal evolution of the boundary layer. The results indicate that the underlying magnetotail magnetic reconnection process was an intrinsically impulsive and the active X-line was located relatively close to the Earth, approximately at 16-18 RE.
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Affiliation(s)
- A. Varsani
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - V. A. Sergeev
- Earth's Physics DepartmentSt. Petersburg State UniversitySt. PetersburgRussia
| | - W. Baumjohann
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - C. J. Owen
- Mullard Space Science Laboratory/UCLDorkingUK
| | | | - Z. Yao
- Space Science Technologies and Astrophysics Research InstituteLiegeBelgium
| | | | - M. V. Kubyshkina
- Earth's Physics DepartmentSt. Petersburg State UniversitySt. PetersburgRussia
| | - T. Sotirelis
- Applied Physics LaboratoryThe Johns Hopkins UniversityBaltimoreMAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - Z. Vörös
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of PhysicsUniversity of GrazGrazAustria
| | - M. Andriopoulou
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - D. J. Gershman
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - L. A. Avanov
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - W. Magnes
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - C. T. Russell
- University of California Los Angeles, IGPP/EPSSLos AngelesCAUSA
| | - F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | | | - B. L. Giles
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - V. N. Coffey
- NASA Marshall Space Flight CenterHuntsvilleALUSA
| | - J. C. Dorelli
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- University of New HampshireDurhamNHUSA
| | | | - R. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
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8
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Russell CT, Strangeway RJ, Zhao C, Anderson BJ, Baumjohann W, Bromund KR, Fischer D, Kepko L, Le G, Magnes W, Nakamura R, Plaschke F, Slavin JA, Torbert RB, Moore TE, Paterson WR, Pollock CJ, Burch JL. Structure, force balance, and topology of Earth's magnetopause. Science 2017; 356:960-963. [PMID: 28572393 DOI: 10.1126/science.aag3112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 01/25/2017] [Accepted: 05/12/2017] [Indexed: 11/02/2022]
Abstract
The magnetopause deflects the solar wind plasma and confines Earth's magnetic field. We combine measurements made by the four spacecraft of the Magnetospheric Multiscale mission to demonstrate how the plasma and magnetic forces at the boundary affect the interaction between the shocked solar wind and Earth's magnetosphere. We compare these forces with the plasma pressure and examine the electron distribution function. We find that the magnetopause has sublayers with thickness comparable to the ion scale. Small pockets of low magnetic field strength, small radius of curvature, and high electric current mark the electron diffusion region. The flow of electrons, parallel and antiparallel to the magnetic field, reveals a complex topology with the creation of magnetic ropes at the boundary.
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Affiliation(s)
- C T Russell
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA.
| | - R J Strangeway
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - C Zhao
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - B J Anderson
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA
| | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - K R Bromund
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D Fischer
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - L Kepko
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.,University of New Hampshire, Durham, NH 03824, USA
| | - G Le
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - J A Slavin
- Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109-2143, USA
| | - R B Torbert
- University of New Hampshire, Durham, NH 03824, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - W R Paterson
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX 78228-0510, USA
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9
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Le G, Chi PJ, Strangeway RJ, Russell CT, Slavin JA, Takahashi K, Singer HJ, Anderson BJ, Bromund K, Fischer D, Kepko EL, Magnes W, Nakamura R, Plaschke F, Torbert RB. Global observations of magnetospheric high- m poloidal waves during the 22 June 2015 magnetic storm. Geophys Res Lett 2017; 44:3456-3464. [PMID: 28713180 PMCID: PMC5488625 DOI: 10.1002/2017gl073048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/06/2017] [Accepted: 04/06/2017] [Indexed: 06/07/2023]
Abstract
We report global observations of high-m poloidal waves during the recovery phase of the 22 June 2015 magnetic storm from a constellation of widely spaced satellites of five missions including Magnetospheric Multiscale (MMS), Van Allen Probes, Time History of Events and Macroscale Interactions during Substorm (THEMIS), Cluster, and Geostationary Operational Environmental Satellites (GOES). The combined observations demonstrate the global spatial extent of storm time poloidal waves. MMS observations confirm high azimuthal wave numbers (m ~ 100). Mode identification indicates the waves are associated with the second harmonic of field line resonances. The wave frequencies exhibit a decreasing trend as L increases, distinguishing them from the single-frequency global poloidal modes normally observed during quiet times. Detailed examination of the instantaneous frequency reveals discrete spatial structures with step-like frequency changes along L. Each discrete L shell has a steady wave frequency and spans about 1 RE , suggesting that there exist a discrete number of drift-bounce resonance regions across L shells during storm times.
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Affiliation(s)
- G. Le
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - P. J. Chi
- Department of Earth, Planetary, and Space Sciences and Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space Sciences and Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space Sciences and Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - J. A. Slavin
- Department of Climate and Space Sciences & EngineeringUniversity of MichiganAnn ArborMichiganUSA
| | - K. Takahashi
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - H. J. Singer
- NOAA Space Weather Prediction CenterBoulderColoradoUSA
| | - B. J. Anderson
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - K. Bromund
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - D. Fischer
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - E. L. Kepko
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - W. Magnes
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - R. Nakamura
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - F. Plaschke
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - R. B. Torbert
- Physics DepartmentUniversity of New HampshireDurhamNew HampshireUSA
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10
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Johlander A, Schwartz SJ, Vaivads A, Khotyaintsev YV, Gingell I, Peng IB, Markidis S, Lindqvist PA, Ergun RE, Marklund GT, Plaschke F, Magnes W, Strangeway RJ, Russell CT, Wei H, Torbert RB, Paterson WR, Gershman DJ, Dorelli JC, Avanov LA, Lavraud B, Saito Y, Giles BL, Pollock CJ, Burch JL. Rippled Quasiperpendicular Shock Observed by the Magnetospheric Multiscale Spacecraft. Phys Rev Lett 2016; 117:165101. [PMID: 27792387 DOI: 10.1103/physrevlett.117.165101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Indexed: 06/06/2023]
Abstract
Collisionless shock nonstationarity arising from microscale physics influences shock structure and particle acceleration mechanisms. Nonstationarity has been difficult to quantify due to the small spatial and temporal scales. We use the closely spaced (subgyroscale), high-time-resolution measurements from one rapid crossing of Earth's quasiperpendicular bow shock by the Magnetospheric Multiscale (MMS) spacecraft to compare competing nonstationarity processes. Using MMS's high-cadence kinetic plasma measurements, we show that the shock exhibits nonstationarity in the form of ripples.
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Affiliation(s)
- A Johlander
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
- Department of Physics and Astronomy, Uppsala University, Uppsala 75120, Sweden
| | - S J Schwartz
- Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - A Vaivads
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | | | - I Gingell
- Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - I B Peng
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - S Markidis
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - R E Ergun
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - G T Marklund
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - R J Strangeway
- University of California, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, California 90095, USA
| | - H Wei
- University of California, Los Angeles, California 90095, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- University of Maryland, College Park, Maryland 20742, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L A Avanov
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, Toulouse 31028, France
- Centre National de la Recherche Scientifique, UMR 5277, Toulouse 31400, France
| | - Y Saito
- Institute of Space and Astronautical Science, JAXA, Sagamihara 2525210, Japan
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
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11
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Schmid D, Nakamura R, Volwerk M, Plaschke F, Narita Y, Baumjohann W, Magnes W, Fischer D, Eichelberger HU, Torbert RB, Russell CT, Strangeway RJ, Leinweber HK, Le G, Bromund KR, Anderson BJ, Slavin JA, Kepko EL. A comparative study of dipolarization fronts at MMS and Cluster. Geophys Res Lett 2016; 43:6012-6019. [PMID: 27478286 PMCID: PMC4949994 DOI: 10.1002/2016gl069520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 05/26/2016] [Indexed: 06/02/2023]
Abstract
We present a statistical study of dipolarization fronts (DFs), using magnetic field data from MMS and Cluster, at radial distances below 12 RE and 20 RE , respectively. Assuming that the DFs have a semicircular cross section and are propelled by the magnetic tension force, we used multispacecraft observations to determine the DF velocities. About three quarters of the DFs propagate earthward and about one quarter tailward. Generally, MMS is in a more dipolar magnetic field region and observes larger-amplitude DFs than Cluster. The major findings obtained in this study are as follows: (1) At MMS ∼57 % of the DFs move faster than 150 km/s, while at Cluster only ∼35 %, indicating a variable flux transport rate inside the flow-braking region. (2) Larger DF velocities correspond to higher Bz values directly ahead of the DFs. We interpret this as a snow plow-like phenomenon, resulting from a higher magnetic flux pileup ahead of DFs with higher velocities.
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Affiliation(s)
- D. Schmid
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- NAWI GrazUniversity of GrazGrazAustria
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - M. Volwerk
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Y. Narita
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - W. Baumjohann
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - W. Magnes
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - D. Fischer
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | | | - R. B. Torbert
- Institute for the Study of Earth, Oceans, and SpaceUniversity of New HampshireDurhamNew HampshireUSA
- Southwest Research InstituteSan AntonioTexasUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - H. K. Leinweber
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - G. Le
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - K. R. Bromund
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - B. J. Anderson
- The Johns Hopkins Applied Physics LaboratoryLaurelMarylandUSA
| | - J. A. Slavin
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMichiganUSA
| | - E. L. Kepko
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
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12
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Nakamura R, Sergeev VA, Baumjohann W, Plaschke F, Magnes W, Fischer D, Varsani A, Schmid D, Nakamura TKM, Russell CT, Strangeway RJ, Leinweber HK, Le G, Bromund KR, Pollock CJ, Giles BL, Dorelli JC, Gershman DJ, Paterson W, Avanov LA, Fuselier SA, Genestreti K, Burch JL, Torbert RB, Chutter M, Argall MR, Anderson BJ, Lindqvist P, Marklund GT, Khotyaintsev YV, Mauk BH, Cohen IJ, Baker DN, Jaynes AN, Ergun RE, Singer HJ, Slavin JA, Kepko EL, Moore TE, Lavraud B, Coffey V, Saito Y. Transient, small-scale field-aligned currents in the plasma sheet boundary layer during storm time substorms. Geophys Res Lett 2016; 43:4841-4849. [PMID: 27867235 PMCID: PMC5111425 DOI: 10.1002/2016gl068768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/26/2016] [Accepted: 05/03/2016] [Indexed: 06/02/2023]
Abstract
We report on field-aligned current observations by the four Magnetospheric Multiscale (MMS) spacecraft near the plasma sheet boundary layer (PSBL) during two major substorms on 23 June 2015. Small-scale field-aligned currents were found embedded in fluctuating PSBL flux tubes near the separatrix region. We resolve, for the first time, short-lived earthward (downward) intense field-aligned current sheets with thicknesses of a few tens of kilometers, which are well below the ion scale, on flux tubes moving equatorward/earthward during outward plasma sheet expansion. They coincide with upward field-aligned electron beams with energies of a few hundred eV. These electrons are most likely due to acceleration associated with a reconnection jet or high-energy ion beam-produced disturbances. The observations highlight coupling of multiscale processes in PSBL as a consequence of magnetotail reconnection.
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13
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Plaschke F, Hietala H, Angelopoulos V, Nakamura R. Geoeffective jets impacting the magnetopause are very common. J Geophys Res Space Phys 2016; 121:3240-3253. [PMID: 27478719 PMCID: PMC4950216 DOI: 10.1002/2016ja022534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 03/22/2016] [Accepted: 03/25/2016] [Indexed: 06/06/2023]
Abstract
The subsolar magnetosheath is penetrated by transient enhancements in dynamic pressure. These enhancements, also called high-speed jets, can propagate to the magnetopause, causing large-amplitude yet localized boundary indentations on impact. Possible downstream consequences of these impacts are, e.g., local magnetopause reconnection, impulsive penetration of magnetosheath plasma into the magnetosphere, inner magnetospheric and boundary surface waves, drop outs and other variations in radiation belt electron populations, ionospheric flow enhancements, and magnetic field variations observed on the ground. Consequently, jets can be geoeffective. The extend of their geoeffectiveness is influenced by the amount of mass, momentum, and energy they transport, i.e., by how large they are. Their overall importance in the framework of solar wind-magnetosphere coupling is determined by how often jets of geoeffective size hit the dayside magnetopause. In this paper, we calculate such jet impact rates for the first time. From a large data set of Time History of Events and Macroscale Interactions during Substorms (THEMIS) multispacecraft jet observations, we find distributions of scale sizes perpendicular and parallel to the direction of jet propagation. They are well modeled by an exponential function with characteristic scales of 1.34RE (perpendicular) and 0.71RE (parallel direction), respectively. Using the distribution of perpendicular scale sizes, we derive an impact rate of jets with cross-sectional diameters larger than 2RE on a reference area of about 100RE2 of the subsolar magnetopause. That rate is about 3 per hour in general, and about 9 per hour under low interplanetary magnetic field cone angle conditions (<30°), which are favorable for jet occurrence in the subsolar magnetosheath.
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Affiliation(s)
- F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - H. Hietala
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - V. Angelopoulos
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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14
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Schmid D, Nakamura R, Plaschke F, Volwerk M, Baumjohann W. Two states of magnetotail dipolarization fronts: A statistical study. J Geophys Res Space Phys 2015; 120:1096-1108. [PMID: 26167443 PMCID: PMC4497466 DOI: 10.1002/2014ja020380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 12/05/2014] [Indexed: 06/02/2023]
Abstract
We study the ion density and temperature in the predipolarization and postdipolarization plasma sheets in the Earth's magnetotail using 9 years (2001-2009) of Cluster data. For our study we selected cases when Cluster observed dipolarization fronts (DFs) with an earthward plasma flow greater than 150km/s. We perform a statistical study of the temperature and density variations during the DF crossings. Earlier studies concluded that on average, the temperature increases while the density decreases across the DF. Our statistical results show a more diverse picture: While ∼54% of the DFs follow this pattern (category A), for ∼28% the temperature decreases while the density increases across the DF (category B). We found an overall decrease in thermal pressure for category A DFs with a more pronounced decrease at the DF duskside, while DFs of category B showed no clear pattern in the pressure change. Both categories are associated with earthward plasma flows but with some difference: (1) category A flows are faster than category B flows, (2) the observations indicate that category B flows are directed perpendicular to the current in the near-Earth current sheet while category A flows are tilted slightly duskward from this direction, and (3) the background Bz of category B is higher than that of category A. Based on these results, we hypothesize that after reconnection takes place, a bursty bulk flow emerges with category A characteristics, and as it travels earthward, it further evolves into category B characteristics, which is in a more dipolarized region with slower plasma flow (closer to the flow-braking region).
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Affiliation(s)
- D Schmid
- Space Research Institute, Austrian Academy of SciencesGraz, Austria
- University of Graz, NAWI GrazGraz, Austria
| | - R Nakamura
- Space Research Institute, Austrian Academy of SciencesGraz, Austria
| | - F Plaschke
- Space Research Institute, Austrian Academy of SciencesGraz, Austria
| | - M Volwerk
- Space Research Institute, Austrian Academy of SciencesGraz, Austria
| | - W Baumjohann
- Space Research Institute, Austrian Academy of SciencesGraz, Austria
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15
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Hietala H, Plaschke F. On the generation of magnetosheath high-speed jets by bow shock ripples. J Geophys Res Space Phys 2013; 118:7237-7245. [PMID: 26167426 PMCID: PMC4497490 DOI: 10.1002/2013ja019172] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/05/2013] [Accepted: 11/02/2013] [Indexed: 06/04/2023]
Abstract
[1]The terrestrial magnetosheath is embedded with coherent high-speed jets of about 1RE in scale, predominantly during quasi-radial interplanetary magnetic field (IMF). When these high dynamic pressure (Pdyn) jets hit the magnetopause, they cause large indentations and further magnetospheric effects. The source of these jets has remained controversial. One of the proposed mechanisms is based on ripples of the quasi-parallel bow shock. In this paper, we combine for the first time, 4 years of subsolar magnetosheath observations from the Time History of Events and Macroscale Interactions during Substorms mission and corresponding NASA/OMNI solar wind conditions with model calculations of a rippled bow shock. Concentrating on the magnetosheath close to the shock during intervals when the angle between the IMF and the Sun-Earth line was small, we find that (1) 97% of the observed jets can be produced by local ripples of the shock under the observed upstream conditions; (2) the coherent jets form a significant fraction of the high Pdyn tail of the magnetosheath flow distribution; (3) the magnetosheath Pdyn distribution matches the flow from a bow shock with ripples that have a dominant amplitude to wavelength ratio of about 9% (∼0.1RE/1RE) and are present ∼12% of the time at any given location.
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Affiliation(s)
- H Hietala
- Blackett Laboratory, Imperial College London London, UK
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences Graz, Austria
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