1
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Kitamura N, Amano T, Omura Y, Boardsen SA, Gershman DJ, Miyoshi Y, Kitahara M, Katoh Y, Kojima H, Nakamura S, Shoji M, Saito Y, Yokota S, Giles BL, Paterson WR, Pollock CJ, Barrie AC, Skeberdis DG, Kreisler S, Le Contel O, Russell CT, Strangeway RJ, Lindqvist PA, Ergun RE, Torbert RB, Burch JL. Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth. Nat Commun 2022; 13:6259. [PMID: 36307443 PMCID: PMC9616889 DOI: 10.1038/s41467-022-33604-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 01/13/2022] [Accepted: 09/22/2022] [Indexed: 11/30/2022] Open
Abstract
Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA’s Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations. Excitation of whistler-mode waves by cyclotron instability is considered as the likely generation process of the waves. Here, the authors show direct observational evidence for locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves in Earth’s magnetosheath.
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Affiliation(s)
- N Kitamura
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan. .,Department of Earth and Planetary Science, Graduate School of Science, the University of Tokyo, Tokyo, Japan.
| | - T Amano
- Department of Earth and Planetary Science, Graduate School of Science, the University of Tokyo, Tokyo, Japan
| | - Y Omura
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan
| | - S A Boardsen
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Goddard Planetary Heliophysics Institute, University of Maryland, Baltimore County, MD, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - Y Miyoshi
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - M Kitahara
- Department of Geophysics, Graduate school of Science, Tohoku University, Sendai, Japan
| | - Y Katoh
- Department of Geophysics, Graduate school of Science, Tohoku University, Sendai, Japan
| | - H Kojima
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan
| | - S Nakamura
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - M Shoji
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - Y Saito
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - S Yokota
- Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | - A C Barrie
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Aurora Engineering, Potomac, MD, USA
| | - D G Skeberdis
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,a.i. solutions Inc, Lanham, MD, USA
| | - S Kreisler
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Aurora Engineering, Potomac, MD, USA
| | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Sorbonne Université/Université Paris-Saclay/Observatoire de Paris/Ecole Polytechnique Institut Polytechnique de Paris, Paris, France
| | - C T Russell
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - R J Strangeway
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | | | - R E Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - R B Torbert
- Department of Physics, University of New Hampshire, Durham, NH, USA.,Southwest Research Institute, San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
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2
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Hasegawa H, Denton RE, Nakamura TKM, Genestreti KJ, Phan TD, Nakamura R, Hwang K, Ahmadi N, Shi QQ, Hesse M, Burch JL, Webster JM, Torbert RB, Giles BL, Gershman DJ, Russell CT, Strangeway RJ, Wei HY, Lindqvist P, Khotyaintsev YV, Ergun RE, Saito Y. Magnetic Field Annihilation in a Magnetotail Electron Diffusion Region With Electron-Scale Magnetic Island. J Geophys Res Space Phys 2022; 127:e2022JA030408. [PMID: 36248013 PMCID: PMC9541864 DOI: 10.1029/2022ja030408] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/27/2022] [Accepted: 06/20/2022] [Indexed: 06/16/2023]
Abstract
We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.
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Affiliation(s)
- H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | - T. K. M. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of PhysicsUniversity of GrazGrazAustria
| | | | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - N. Ahmadi
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
| | - Q. Q. Shi
- Shandong Provincial Key Laboratory of Optical Astronomy and Solar‐Terrestrial EnvironmentInstitute of Space SciencesShandong UniversityWeihaiChina
| | - M. Hesse
- NASA Ames Research CenterMoffett FieldCAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - R. B. Torbert
- Institute of PhysicsUniversity of GrazGrazAustria
- Physics DepartmentUniversity of New HampshireDurhamNHUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - H. Y. Wei
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | | | | | - R. E. Ergun
- Department of Astrophysical and Planetary SciencesUniversity of ColoradoBoulderCOUSA
| | - Y. Saito
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
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3
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Cozzani G, Khotyaintsev YV, Graham DB, Egedal J, André M, Vaivads A, Alexandrova A, Le Contel O, Nakamura R, Fuselier SA, Russell CT, Burch JL. Structure of a Perturbed Magnetic Reconnection Electron Diffusion Region in the Earth's Magnetotail. Phys Rev Lett 2021; 127:215101. [PMID: 34860109 DOI: 10.1103/physrevlett.127.215101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 09/22/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
We report in situ observations of an electron diffusion region (EDR) and adjacent separatrix region in the Earth's magnetotail. We observe significant magnetic field oscillations near the lower hybrid frequency which propagate perpendicularly to the reconnection plane. We also find that the strong electron-scale gradients close to the EDR exhibit significant oscillations at a similar frequency. Such oscillations are not expected for a crossing of a steady 2D EDR, and can be explained by a complex motion of the reconnection plane induced by current sheet kinking propagating in the out-of-reconnection-plane direction. Thus, all three spatial dimensions have to be taken into account to explain the observed perturbed EDR crossing. These results shed light on the interplay between magnetic reconnection and current sheet drift instabilities in electron-scale current sheets and highlight the need for adopting a 3D description of the EDR, going beyond the two-dimensional and steady-state conception of reconnection.
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Affiliation(s)
- G Cozzani
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | | | - D B Graham
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | - J Egedal
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - M André
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | - A Vaivads
- Space and Plasma Physics, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - A Alexandrova
- Laboratoire de Physique des Plasmas, CNRS, Sorbonne Université, Université Paris-Saclay, Observatoire de Paris, École Polytechnique Institut Polytechnique de Paris, Palaiseau 91128, France
| | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS, Sorbonne Université, Université Paris-Saclay, Observatoire de Paris, École Polytechnique Institut Polytechnique de Paris, Palaiseau 91128, France
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - S A Fuselier
- Southwest Research Institute, San Antonio, Texas 78238, USA
- University of Texas at San Antonio, San Antonio, Texas 78249, USA
| | - C T Russell
- University of California, Los Angeles, California 90095, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
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4
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Vines SK, Anderson BJ, Allen RC, Denton RE, Engebretson MJ, Johnson JR, Toledo‐Redondo S, Lee JH, Turner DL, Ergun RE, Strangeway RJ, Russell CT, Wei H, Torbert RB, Fuselier SA, Giles BL, Burch JL. Determining EMIC Wave Vector Properties Through Multi-Point Measurements: The Wave Curl Analysis. J Geophys Res Space Phys 2021; 126:e2020JA028922. [PMID: 33868890 PMCID: PMC8047877 DOI: 10.1029/2020ja028922] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/08/2021] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Electromagnetic ion cyclotron (EMIC) waves play important roles in particle loss processes in the magnetosphere. Determining the evolution of EMIC waves as they propagate and how this evolution affects wave-particle interactions requires accurate knowledge of the wave vector, k. We present a technique using the curl of the wave magnetic field to determine k observationally, enabled by the unique configuration and instrumentation of the Magnetospheric MultiScale (MMS) spacecraft. The wave curl analysis is demonstrated for synthetic arbitrary electromagnetic waves with varying properties typical of observed EMIC waves. The method is also applied to an EMIC wave interval observed by MMS on October 28, 2015. The derived wave properties and k from the wave curl analysis for the observed EMIC wave are compared with the Waves in Homogenous, Anisotropic, Multi-component Plasma (WHAMP) wave dispersion solution and with results from other single- and multi-spacecraft techniques. We find good agreement between k from the wave curl analysis, k determined from other observational techniques, and k determined from WHAMP. Additionally, the variation of k due to the time and frequency intervals used in the wave curl analysis is explored. This exploration demonstrates that the method is robust when applied to a wave containing at least 3-4 wave periods and over a rather wide frequency range encompassing the peak wave emission. These results provide confidence that we are able to directly determine the wave vector properties using this multi-spacecraft method implementation, enabling systematic studies of EMIC wave k properties with MMS.
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Affiliation(s)
- S. K. Vines
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - B. J. Anderson
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. C. Allen
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | | | - J. R. Johnson
- Department of EngineeringAndrews UniversityBerrien SpringsMIUSA
| | - S. Toledo‐Redondo
- Department of Electromagnetism and ElectronicsUniversity of MurciaMurciaSpain
| | - J. H. Lee
- The Aerospace CorporationEl SegundoCAUSA
| | - D. L. Turner
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado at BoulderBoulderCOUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesInstitute for Geophysics and Planetary PhysicsUniversity of California at Los AngelesLos AngelesCAUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesInstitute for Geophysics and Planetary PhysicsUniversity of California at Los AngelesLos AngelesCAUSA
| | - H. Wei
- Department of Earth, Planetary, and Space SciencesInstitute for Geophysics and Planetary PhysicsUniversity of California at Los AngelesLos AngelesCAUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
- Southwest Research InstituteSan AntonioTXUSA
| | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
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5
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Eastwood JP, Goldman MV, Phan TD, Stawarz JE, Cassak PA, Drake JF, Newman D, Lavraud B, Shay MA, Ergun RE, Burch JL, Gershman DJ, Giles BL, Lindqvist PA, Torbert RB, Strangeway RJ, Russell CT. Energy Flux Densities near the Electron Dissipation Region in Asymmetric Magnetopause Reconnection. Phys Rev Lett 2020; 125:265102. [PMID: 33449730 DOI: 10.1103/physrevlett.125.265102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 10/29/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Magnetic reconnection is of fundamental importance to plasmas because of its role in releasing and repartitioning stored magnetic energy. Previous results suggest that this energy is predominantly released as ion enthalpy flux along the reconnection outflow. Using Magnetospheric Multiscale data we find the existence of very significant electron energy flux densities in the vicinity of the magnetopause electron dissipation region, orthogonal to the ion energy outflow. These may significantly impact models of electron transport, wave generation, and particle acceleration.
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Affiliation(s)
- J P Eastwood
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - M V Goldman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J E Stawarz
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - P A Cassak
- Department of Physics and Astronomy and Center for KINETIC Plasma Physics, West Virginia University, Morgantown, West Virginia 26506, USA
| | - J F Drake
- Department of Physics/Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
| | - D Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - B Lavraud
- Laboratoire d'Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France
- Institut de Recherche en Astrophysique et Planétologie, CNRS, CNES, Université de Toulouse, 31028 Toulouse Cedex 4, France
| | - M A Shay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - R E Ergun
- LASP/Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - D J Gershman
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - P A Lindqvist
- KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - R B Torbert
- Southwest Research Institute, San Antonio, Texas 78238, USA
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - R J Strangeway
- Institute of Geophysics, Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- Institute of Geophysics, Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095, USA
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6
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Scully JEC, Schenk PM, Castillo-Rogez JC, Buczkowski DL, Williams DA, Pasckert JH, Duarte KD, Romero VN, Quick LC, Sori MM, Landis ME, Raymond CA, Neesemann A, Schmidt BE, Sizemore HG, Russell CT. The varied sources of faculae-forming brines in Ceres' Occator crater emplaced via hydrothermal brine effusion. Nat Commun 2020; 11:3680. [PMID: 32778642 PMCID: PMC7417532 DOI: 10.1038/s41467-020-15973-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 04/06/2020] [Indexed: 11/23/2022] Open
Abstract
Before acquiring highest-resolution data of Ceres, questions remained about the emplacement mechanism and source of Occator crater's bright faculae. Here we report that brine effusion emplaced the faculae in a brine-limited, impact-induced hydrothermal system. Impact-derived fracturing enabled brines to reach the surface. The central faculae, Cerealia and Pasola Facula, postdate the central pit, and were primarily sourced from an impact-induced melt chamber, with some contribution from a deeper, pre-existing brine reservoir. Vinalia Faculae, in the crater floor, were sourced from the laterally extensive deep reservoir only. Vinalia Faculae are comparatively thinner and display greater ballistic emplacement than the central faculae because the deep reservoir brines took a longer path to the surface and contained more gas than the shallower impact-induced melt chamber brines. Impact-derived fractures providing conduits, and mixing of impact-induced melt with deeper endogenic brines, could also allow oceanic material to reach the surfaces of other large icy bodies.
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Affiliation(s)
- J E C Scully
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.
| | - P M Schenk
- Lunar and Planetary Institute, Houston, TX, USA
| | - J C Castillo-Rogez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - D L Buczkowski
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - D A Williams
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA
| | - J H Pasckert
- Institute für Planetologie, University of Münster, Münster, Germany
| | - K D Duarte
- Georgia Institute of Technology, Atlanta, GA, USA
| | - V N Romero
- Georgia Institute of Technology, Atlanta, GA, USA
| | - L C Quick
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - M M Sori
- Lunar and Planetary Laboratory, Tucson, AZ, USA
| | - M E Landis
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO, USA
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - A Neesemann
- Free University of Berlin, 14195, Berlin, Germany
| | - B E Schmidt
- Georgia Institute of Technology, Atlanta, GA, USA
| | | | - C T Russell
- University of California, Los Angeles, CA, USA
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7
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Schenk P, Scully J, Buczkowski D, Sizemore H, Schmidt B, Pieters C, Neesemann A, O'Brien D, Marchi S, Williams D, Nathues A, De Sanctis M, Tosi F, Russell CT, Castillo-Rogez J, Raymond C. Impact heat driven volatile redistribution at Occator crater on Ceres as a comparative planetary process. Nat Commun 2020; 11:3679. [PMID: 32778649 PMCID: PMC7417549 DOI: 10.1038/s41467-020-17184-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 06/16/2020] [Indexed: 12/02/2022] Open
Abstract
Hydrothermal processes in impact environments on water-rich bodies such as Mars and Earth are relevant to the origins of life. Dawn mapping of dwarf planet (1) Ceres has identified similar deposits within Occator crater. Here we show using Dawn high-resolution stereo imaging and topography that Ceres' unique composition has resulted in widespread mantling by solidified water- and salt-rich mud-like impact melts with scattered endogenic pits, troughs, and bright mounds indicative of outgassing of volatiles and periglacial-style activity during solidification. These features are distinct from and less extensive than on Mars, indicating that Occator melts may be less gas-rich or volatiles partially inhibited from reaching the surface. Bright salts at Vinalia Faculae form thin surficial precipitates sourced from hydrothermal brine effusion at many individual sites, coalescing in several larger centers, but their ages are statistically indistinguishable from floor materials, allowing for but not requiring migration of brines from deep crustal source(s).
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Affiliation(s)
- P Schenk
- Lunar and Planetary Institute/USRA, Houston, TX, USA.
| | - J Scully
- Jet Propulsion Laboratory/Caltech, Pasadena, CA, USA
| | - D Buczkowski
- Johns Hopkins University-Applied Physics Laboratory, Laurel, MD, USA
| | - H Sizemore
- Planetary Science Institute, Tucson, AZ, USA
| | - B Schmidt
- Georgia Institute of Technology, Atlanta, GA, USA
| | - C Pieters
- Brown University Providence, Providence, RI, USA
| | | | - D O'Brien
- Planetary Science Institute, Tucson, AZ, USA
| | - S Marchi
- Southwest Research Institute, Boulder, CO, USA
| | - D Williams
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA
| | - A Nathues
- Max Planck Institute for Solar System Research, Goettingen, Germany
| | - M De Sanctis
- Istituto di Astrofisica e Planetologia Spaziali, INAF, Rome, Italy
| | - F Tosi
- Istituto di Astrofisica e Planetologia Spaziali, INAF, Rome, Italy
| | - C T Russell
- University of California, Los Angeles, CA, USA
| | | | - C Raymond
- Jet Propulsion Laboratory/Caltech, Pasadena, CA, USA
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8
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Chen LJ, Wang S, Le Contel O, Rager A, Hesse M, Drake J, Dorelli J, Ng J, Bessho N, Graham D, Wilson LB, Moore T, Giles B, Paterson W, Lavraud B, Genestreti K, Nakamura R, Khotyaintsev YV, Ergun RE, Torbert RB, Burch J, Pollock C, Russell CT, Lindqvist PA, Avanov L. Lower-Hybrid Drift Waves Driving Electron Nongyrotropic Heating and Vortical Flows in a Magnetic Reconnection Layer. Phys Rev Lett 2020; 125:025103. [PMID: 32701350 DOI: 10.1103/physrevlett.125.025103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 06/11/2020] [Indexed: 06/11/2023]
Abstract
We report measurements of lower-hybrid drift waves driving electron heating and vortical flows in an electron-scale reconnection layer under a guide field. Electrons accelerated by the electrostatic potential of the waves exhibit perpendicular and nongyrotropic heating. The vortical flows generate magnetic field perturbations comparable to the guide field magnitude. The measurements reveal a new regime of electron-wave interaction and how this interaction modifies the electron dynamics in the reconnection layer.
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Affiliation(s)
- L-J Chen
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - S Wang
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- University of Maryland, College Park, Maryland 20747, USA
| | - O Le Contel
- CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris F91128, France
| | - A Rager
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M Hesse
- University of Bergen, Bergen 5020, Norway
| | - J Drake
- University of Maryland, College Park, Maryland 20747, USA
| | - J Dorelli
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - J Ng
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- University of Maryland, College Park, Maryland 20747, USA
| | - N Bessho
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- University of Maryland, College Park, Maryland 20747, USA
| | - D Graham
- Swedish Institute of Space Physics, Uppsala SE-75121, Sweden
| | - Lynn B Wilson
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - T Moore
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - W Paterson
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse (UPS), CNRS, CNES, Toulouse 31027 Cedex 4, France
| | - K Genestreti
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz A-8042, Austria
| | | | - R E Ergun
- University of Colorado, Boulder, Colorado 80305, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - J Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - C Pollock
- Denali Scientific, Healy, Alaska 99743, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm SE-11428, Sweden
| | - L Avanov
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- University of Maryland, College Park, Maryland 20747, USA
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9
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Russell CT, Rees EJ. An open-hardware sample mounting solution for inverted light-sheet microscopes with large detection objective lenses. J Microsc 2020; 280:63-68. [PMID: 32617967 DOI: 10.1111/jmi.12940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/27/2020] [Accepted: 06/25/2020] [Indexed: 01/22/2023]
Abstract
Implementations of light-sheet microscopes are often incompatible with standard methods of sample mounting. Light-sheet microscopy uses orthogonal illumination and detection to create a thin sheet of light which does not illuminate the sample outside of the depth of field of the detection axis. Typically, this configuration involves a pair of orthogonal objectives which constrains the positioning and length of cover slips in the range of the detection objective. Here, we present an open-hardware sample mounting system for light-sheet microscopes using large detection objectives, built using 3D printed components and demonstrate the chamber's efficacy on live biological samples in a custom light-sheet microscope. LAY DESCRIPTION: Implementations of light-sheet microscopes are often incompatible with standard methods of sample mounting. Light-sheet microscopy creates a thin sheet of light at a certain depth of field within a volumetric sample. Typically, this configuration involves a pair of orthogonal objectives which constrains the positioning of samples and sample-mounting apparatus in range of the detection objective. To overcome the limitations of this setup, we present an open-hardware sample mounting system for light-sheet microscopes using large detection objectives, built using 3D printed components and demonstrate the chamber's efficacy on live biological samples in a custom light-sheet microscope.
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Affiliation(s)
- C T Russell
- Department of Chemical Engineering and Biotechnology, Cambridge University, Cambridge, U.K
- European Bio-informatics Institute, Cambridge, U.K
| | - E J Rees
- Department of Chemical Engineering and Biotechnology, Cambridge University, Cambridge, U.K
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10
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Petrinec SM, Burch JL, Chandler M, Farrugia CJ, Fuselier SA, Giles BL, Gomez RG, Mukherjee J, Paterson WR, Russell CT, Sibeck DG, Strangeway RJ, Torbert RB, Trattner KJ, Vines SK, Zhao C. Characteristics of Minor Ions and Electrons in Flux Transfer Events Observed by the Magnetospheric Multiscale Mission. J Geophys Res Space Phys 2020; 125:e2020JA027778. [PMID: 32999806 PMCID: PMC7507212 DOI: 10.1029/2020ja027778] [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: 01/07/2020] [Revised: 03/18/2020] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.
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Affiliation(s)
- S. M. Petrinec
- Lockheed Martin Advanced Technology CenterPalo AltoCAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - M. Chandler
- NASA Marshall Space Flight CenterHuntsvilleALUSA
| | - C. J. Farrugia
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - R. G. Gomez
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | | | | | - C. T. Russell
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | | | - R. J. Strangeway
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - K. J. Trattner
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - S. K. Vines
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - C. Zhao
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
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11
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Hwang K, Dokgo K, Choi E, Burch JL, Sibeck DG, Giles BL, Hasegawa H, Fu HS, Liu Y, Wang Z, Nakamura TKM, Ma X, Fear RC, Khotyaintsev Y, Graham DB, Shi QQ, Escoubet CP, Gershman DJ, Paterson WR, Pollock CJ, Ergun RE, Torbert RB, Dorelli JC, Avanov L, Russell CT, Strangeway RJ. Magnetic Reconnection Inside a Flux Rope Induced by Kelvin-Helmholtz Vortices. J Geophys Res Space Phys 2020; 125:e2019JA027665. [PMID: 32714734 PMCID: PMC7375157 DOI: 10.1029/2019ja027665] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/29/2020] [Accepted: 03/03/2020] [Indexed: 06/11/2023]
Abstract
On 5 May 2017, MMS observed a crater-type flux rope on the dawnside tailward magnetopause with fluctuations. The boundary-normal analysis shows that the fluctuations can be attributed to nonlinear Kelvin-Helmholtz (KH) waves. Reconnection signatures such as flow reversals and Joule dissipation were identified at the leading and trailing edges of the flux rope. In particular, strong northward electron jets observed at the trailing edge indicated midlatitude reconnection associated with the 3-D structure of the KH vortex. The scale size of the flux rope, together with reconnection signatures, strongly supports the interpretation that the flux rope was generated locally by KH vortex-induced reconnection. The center of the flux rope also displayed signatures of guide-field reconnection (out-of-plane electron jets, parallel electron heating, and Joule dissipation). These signatures indicate that an interface between two interlinked flux tubes was undergoing interaction, causing a local magnetic depression, resulting in an M-shaped crater flux rope, as supported by reconstruction.
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Affiliation(s)
- K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - K. Dokgo
- Southwest Research InstituteSan AntonioTXUSA
| | - E. Choi
- Southwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | - H. S. Fu
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | - Y. Liu
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | - Z. Wang
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | | | - X. Ma
- Physical Sciences DepartmentEmbry‐Riddle Aeronautical UniversityDaytona BeachFLUSA
| | - R. C. Fear
- School of Physics and AstronomyUniversity of SouthamptonSouthamptonUK
| | | | | | - Q. Q. Shi
- School of Earth and Space SciencesPeking UniversityPekingChina
| | - C. P. Escoubet
- European Space Research and Technology CentreNoordwijkthe Netherlands
| | | | | | | | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado at BoulderBoulderCOUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | | | - L. Avanov
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- The Goddard Planetary Heliophysics InstituteUniversity of Maryland, Baltimore CountyBaltimoreMDUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of California, Los AngelesLos AngelesCAUSA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary PhysicsUniversity of California, Los AngelesLos AngelesCAUSA
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12
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Elkins‐Tanton LT, Asphaug E, Bell JF, Bercovici H, Bills B, Binzel R, Bottke WF, Dibb S, Lawrence DJ, Marchi S, McCoy TJ, Oran R, Park RS, Peplowski PN, Polanskey CA, Prettyman TH, Russell CT, Schaefer L, Weiss BP, Wieczorek MA, Williams DA, Zuber MT. Observations, Meteorites, and Models: A Preflight Assessment of the Composition and Formation of (16) Psyche. J Geophys Res Planets 2020; 125:e2019JE006296. [PMID: 32714727 PMCID: PMC7375145 DOI: 10.1029/2019je006296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/29/2020] [Accepted: 01/29/2020] [Indexed: 06/02/2023]
Abstract
Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m-3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low-iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron-rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma-ray spectrometer) will produce data sets that distinguish among the models.
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Affiliation(s)
| | | | | | | | - B. Bills
- Jet Propulsion LaboratoryPasadenaCAUSA
| | - R. Binzel
- Massachusetts Institute of TechnologyCambridgeMAUSA
| | | | - S. Dibb
- Arizona State UniversityPhoenixAZUSA
| | | | - S. Marchi
- Southwest Research InstituteBoulderCOUSA
| | | | - R. Oran
- Massachusetts Institute of TechnologyCambridgeMAUSA
| | | | | | | | | | | | | | - B. P. Weiss
- Massachusetts Institute of TechnologyCambridgeMAUSA
| | - M. A. Wieczorek
- Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Université Côte d'AzurNiceFrance
| | | | - M. T. Zuber
- Massachusetts Institute of TechnologyCambridgeMAUSA
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13
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Amano T, Katou T, Kitamura N, Oka M, Matsumoto Y, Hoshino M, Saito Y, Yokota S, Giles BL, Paterson WR, Russell CT, Le Contel O, Ergun RE, Lindqvist PA, Turner DL, Fennell JF, Blake JB. Observational Evidence for Stochastic Shock Drift Acceleration of Electrons at the Earth's Bow Shock. Phys Rev Lett 2020; 124:065101. [PMID: 32109113 DOI: 10.1103/physrevlett.124.065101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/18/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.
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Affiliation(s)
- T Amano
- Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033, Japan
| | - T Katou
- Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033, Japan
| | - N Kitamura
- Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033, Japan
| | - M Oka
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - Y Matsumoto
- Department of Physics, Chiba University, Chiba 263-8522, Japan
| | - M Hoshino
- Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033, Japan
| | - Y Saito
- Institute of Space and Astronautical Science, Sagamihara 252-5210, Japan
| | - S Yokota
- Department of Earth and Space Science, Osaka University, Toyonaka 560-0043, Japan
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C T Russell
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California 90095, USA
| | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris-Sud/Obs. de Paris, Paris F-75252, France
| | - R E Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - D L Turner
- Space Sciences Department, The Aerospace Corporation, El Segundo, California 90245, USA
| | - J F Fennell
- Space Sciences Department, The Aerospace Corporation, El Segundo, California 90245, USA
| | - J B Blake
- Space Sciences Department, The Aerospace Corporation, El Segundo, California 90245, USA
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14
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Khotyaintsev YV, Graham DB, Steinvall K, Alm L, Vaivads A, Johlander A, Norgren C, Li W, Divin A, Fu HS, Hwang KJ, Burch JL, Ahmadi N, Le Contel O, Gershman DJ, Russell CT, Torbert RB. Electron Heating by Debye-Scale Turbulence in Guide-Field Reconnection. Phys Rev Lett 2020; 124:045101. [PMID: 32058767 DOI: 10.1103/physrevlett.124.045101] [Citation(s) in RCA: 2] [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: 08/05/2019] [Revised: 11/22/2019] [Indexed: 06/10/2023]
Abstract
We report electrostatic Debye-scale turbulence developing within the diffusion region of asymmetric magnetopause reconnection with a moderate guide field using observations by the Magnetospheric Multiscale mission. We show that Buneman waves and beam modes cause efficient and fast thermalization of the reconnection electron jet by irreversible phase mixing, during which the jet kinetic energy is transferred into thermal energy. Our results show that the reconnection diffusion region in the presence of a moderate guide field is highly turbulent, and that electrostatic turbulence plays an important role in electron heating.
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Affiliation(s)
| | - D B Graham
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | - K Steinvall
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | - L Alm
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | - A Vaivads
- Department of Space and Plasma Physics, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - A Johlander
- Department of Physics, University of Helsinki, Helsinki 00014, Finland
| | - C Norgren
- University of Bergen, Bergen 5007, Norway
| | - W Li
- State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
| | - A Divin
- Earth Physics Department, St. Petersburg State University, St. Petersburg 198504, Russia
| | - H S Fu
- School of Space and Environment, Beihang University, Beijing 100083, China
| | - K-J Hwang
- Southwest Research Institute, San Antonio, Texas 78228, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78228, USA
| | - N Ahmadi
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS, Ecole Polytechnique, Sorbonne Université, Université Paris-Sud, and Observatoire de Paris, Paris, F-75252 Paris Cedex 05, France
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C T Russell
- University of California, Los Angeles, California 90095, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
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15
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Duarte KD, Schmidt BE, Chilton HT, Hughson KHG, Sizemore HG, Ferrier KL, Buffo JJ, Scully JEC, Nathues A, Platz T, Landis M, Byrne S, Bland M, Russell CT, Raymond CA. Landslides on Ceres: Diversity and Geologic Context. J Geophys Res Planets 2019; 124:3329-3343. [PMID: 32355585 PMCID: PMC7185231 DOI: 10.1029/2018je005673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 08/20/2019] [Accepted: 08/30/2019] [Indexed: 06/11/2023]
Abstract
Landslides are among the most widespread geologic features on Ceres. Using data from Dawn's Framing Camera, landslides were previously classified based upon geomorphologic characteristics into one of three archetypal categories, Type 1(T1), Type 2 (T2), and Type 3 (T3). Due to their geologic context, variation in age, and physical characteristics, most landslides on Ceres are, however, intermediate in their morphology and physical properties between the archetypes of each landslide class. Here we describe the varied morphology of individual intermediate landslides, identify geologic controls that contribute to this variation, and provide first-order quantification of the physical properties of the continuum of Ceres's surface flows. These intermediate flows appear in varied settings and show a range of characteristics, including those found at contacts between craters, those having multiple trunks or lobes; showing characteristics of both T2 and T3 landslides; material slumping on crater rims; very small, ejecta-like flows; and those appearing inside of catenae. We suggest that while their morphologies can vary, the distribution and mechanical properties of intermediate landslides do not differ significantly from that of archetypal landslides, confirming a link between landslides and subsurface ice. We also find that most intermediate landslides are similar to Type 2 landslides and formed by shallow failure. Clusters of these features suggest ice enhancement near Juling, Kupalo and Urvara craters. Since the majority of Ceres's landslides fall in the intermediate landslide category, placing their attributes in context contributes to a better understanding of Ceres's shallow subsurface and the nature of ground ice.
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Affiliation(s)
- K. D. Duarte
- School of Earth and Atmospheric SciencesGeorgia Institute of TechnologyAtlantaGAUSA
| | - B. E. Schmidt
- School of Earth and Atmospheric SciencesGeorgia Institute of TechnologyAtlantaGAUSA
| | - H. T. Chilton
- School of Earth and Atmospheric SciencesGeorgia Institute of TechnologyAtlantaGAUSA
| | - K. H. G. Hughson
- School of Earth and Atmospheric SciencesGeorgia Institute of TechnologyAtlantaGAUSA
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | | | - K. L. Ferrier
- School of Earth and Atmospheric SciencesGeorgia Institute of TechnologyAtlantaGAUSA
| | - J. J. Buffo
- School of Earth and Atmospheric SciencesGeorgia Institute of TechnologyAtlantaGAUSA
| | - J. E. C. Scully
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - A. Nathues
- Max‐Planck Institute for Solar System ResearchKatlenburg‐LindauGermany
| | - T. Platz
- Max‐Planck Institute for Solar System ResearchKatlenburg‐LindauGermany
| | - M. Landis
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
- USGSFlagstaffAZUSA
| | - S. Byrne
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | - M. Bland
- Now at Boulder Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - C. A. Raymond
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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16
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Hwang K, Choi E, Dokgo K, Burch JL, Sibeck DG, Giles BL, Goldstein ML, Paterson WR, Pollock CJ, Shi QQ, Fu H, Hasegawa H, Gershman DJ, Khotyaintsev Y, Torbert RB, Ergun RE, Dorelli JC, Avanov L, Russell CT, Strangeway RJ. Electron Vorticity Indicative of the Electron Diffusion Region of Magnetic Reconnection. Geophys Res Lett 2019; 46:6287-6296. [PMID: 31598018 PMCID: PMC6774273 DOI: 10.1029/2019gl082710] [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: 03/05/2019] [Revised: 05/08/2019] [Accepted: 05/28/2019] [Indexed: 06/10/2023]
Abstract
While vorticity defined as the curl of the velocity has been broadly used in fluid and plasma physics, this quantity has been underutilized in space physics due to low time resolution observations. We report Magnetospheric Multiscale (MMS) observations of enhanced electron vorticity in the vicinity of the electron diffusion region of magnetic reconnection. On 11 July 2017 MMS traversed the magnetotail current sheet, observing tailward-to-earthward outflow reversal, current-carrying electron jets in the direction along the electron meandering motion or out-of-plane direction, agyrotropic electron distribution functions, and dissipative signatures. At the edge of the electron jets, the electron vorticity increased with magnitudes greater than the electron gyrofrequency. The out-of-plane velocity shear along distance from the current sheet leads to the enhanced vorticity. This, in turn, contributes to the magnetic field perturbations observed by MMS. These observations indicate that electron vorticity can act as a proxy for delineating the electron diffusion region of magnetic reconnection.
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Affiliation(s)
- K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - E. Choi
- Southwest Research InstituteSan AntonioTXUSA
| | - K. Dokgo
- Southwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - M. L. Goldstein
- The Goddard Planetary Heliophysics InstituteUniversity of MarylandBaltimoreMDUSA
| | | | | | - Q. Q. Shi
- School of Earth and Space SciencesPeking UniversityPekingChina
| | - H. Fu
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | - H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | | | | | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | | | - L. Avanov
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- The Goddard Planetary Heliophysics InstituteUniversity of MarylandBaltimoreMDUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
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17
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Vines SK, Allen RC, Anderson BJ, Engebretson MJ, Fuselier SA, Russell CT, Strangeway RJ, Ergun RE, Lindqvist PA, Torbert RB, Burch JL. EMIC Waves in the Outer Magnetosphere: Observations of an Off-Equator Source Region. Geophys Res Lett 2019; 46:5707-5716. [PMID: 31423036 PMCID: PMC6686711 DOI: 10.1029/2019gl082152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/03/2019] [Accepted: 05/10/2019] [Indexed: 06/10/2023]
Abstract
Electromagnetic ion cyclotron (EMIC) waves at large L shells were observed away from the magnetic equator by the Magnetospheric MultiScale (MMS) mission nearly continuously for over four hours on 28 October 2015. During this event, the wave Poynting vector direction systematically changed from parallel to the magnetic field (toward the equator), to bidirectional, to antiparallel (away from the equator). These changes coincide with the shift in the location of the minimum in the magnetic field in the southern hemisphere from poleward to equatorward of MMS. The local plasma conditions measured with the EMIC waves also suggest that the outer magnetospheric region sampled during this event was generally unstable to EMIC wave growth. Together, these observations indicate that the bidirectionally propagating wave packets were not a result of reflection at high latitudes but that MMS passed through an off-equator EMIC wave source region associated with the local minimum in the magnetic field.
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Affiliation(s)
- S. K. Vines
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. C. Allen
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - B. J. Anderson
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | | | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
- Institute for Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
- Institute for Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado at BoulderBoulderCOUSA
| | - P. A. Lindqvist
- Department of Space and Plasma PhysicsRoyal Institute of TechnologyStockholmSweden
| | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
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18
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Cozzani G, Retinò A, Califano F, Alexandrova A, Le Contel O, Khotyaintsev Y, Vaivads A, Fu HS, Catapano F, Breuillard H, Ahmadi N, Lindqvist PA, Ergun RE, Torbert RB, Giles BL, Russell CT, Nakamura R, Fuselier S, Mauk BH, Moore T, Burch JL. In situ spacecraft observations of a structured electron diffusion region during magnetopause reconnection. Phys Rev E 2019; 99:043204. [PMID: 31108651 DOI: 10.1103/physreve.99.043204] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Indexed: 11/07/2022]
Abstract
The electron diffusion region (EDR) is the region where magnetic reconnection is initiated and electrons are energized. Because of experimental difficulties, the structure of the EDR is still poorly understood. A key question is whether the EDR has a homogeneous or patchy structure. Here we report Magnetospheric Multiscale (MMS) spacecraft observations providing evidence of inhomogeneous current densities and energy conversion over a few electron inertial lengths within an EDR at the terrestrial magnetopause, suggesting that the EDR can be rather structured. These inhomogenenities are revealed through multipoint measurements because the spacecraft separation is comparable to a few electron inertial lengths, allowing the entire MMS tetrahedron to be within the EDR most of the time. These observations are consistent with recent high-resolution and low-noise kinetic simulations.
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Affiliation(s)
- Giulia Cozzani
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université, Université Paris Sud, Observatoire de Paris, 91128 Palaiseau, France.,Dipartimento di Fisica "E. Fermi", Università di Pisa, I-56127 Pisa, Italy
| | - A Retinò
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université, Université Paris Sud, Observatoire de Paris, 91128 Palaiseau, France
| | - F Califano
- Dipartimento di Fisica "E. Fermi", Università di Pisa, I-56127 Pisa, Italy
| | - A Alexandrova
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université, Université Paris Sud, Observatoire de Paris, 91128 Palaiseau, France
| | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université, Université Paris Sud, Observatoire de Paris, 91128 Palaiseau, France
| | - Y Khotyaintsev
- Swedish Institute of Space Physics, SE-75121 Uppsala, Sweden
| | - A Vaivads
- Swedish Institute of Space Physics, SE-75121 Uppsala, Sweden
| | - H S Fu
- School of Space and Environment, Beihang University, Beijing, 100083, P.R. China
| | - F Catapano
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université, Université Paris Sud, Observatoire de Paris, 91128 Palaiseau, France.,Dipartimento di Fisica, Università della Calabria, I-87036, Arcavacata di Rende (CS), Italy
| | - H Breuillard
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université, Université Paris Sud, Observatoire de Paris, 91128 Palaiseau, France.,Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, CNRS-Université d'Orléans, UMR 7328, 45071 Orléans, France
| | - N Ahmadi
- Laboratory of Atmospheric and Space Physics, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, SE-10044, Stockholm, Sweden
| | - R E Ergun
- Laboratory of Atmospheric and Space Physics, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - R B Torbert
- Space Science Center, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C T Russell
- Department of Earth and Space Sciences, University of California, Los Angeles, California 90095, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, 8042 Graz, Austria
| | - S Fuselier
- Southwest Research Institute, San Antonio, Texas 78238, USA.,University of Texas at San Antonio, San Antonio, Texas 78238, USA
| | - B H Mauk
- The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland 20723, USA
| | - T Moore
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
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19
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Phan TD, Eastwood JP, Shay MA, Drake JF, Sonnerup BUÖ, Fujimoto M, Cassak PA, Øieroset M, Burch JL, Torbert RB, Rager AC, Dorelli JC, Gershman DJ, Pollock C, Pyakurel PS, Haggerty CC, Khotyaintsev Y, Lavraud B, Saito Y, Oka M, Ergun RE, Retino A, Le Contel O, Argall MR, Giles BL, Moore TE, Wilder FD, Strangeway RJ, Russell CT, Lindqvist PA, Magnes W. Publisher Correction: Electron magnetic reconnection without ion coupling in Earth's turbulent magnetosheath. Nature 2019; 569:E9. [PMID: 31073227 DOI: 10.1038/s41586-019-1208-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Change history: In this Letter, the y-axis values in Fig. 3f should go from 4 to -8 (rather than from 4 to -4), the y-axis values in Fig. 3h should appear next to the major tick marks (rather than the minor ticks), and in Fig. 1b, the arrows at the top and bottom of the electron-scale current sheet were going in the wrong direction; these errors have been corrected online.
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Affiliation(s)
- T D Phan
- Space Sciences Laboratory, University of California, Berkeley, CA, USA.
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, London, UK
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | - J F Drake
- University of Maryland, College Park, MD, USA
| | | | | | - P A Cassak
- West Virginia University, Morgantown, WV, USA
| | - M Øieroset
- Space Sciences Laboratory, University of California, Berkeley, CA, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
| | - R B Torbert
- University of New Hampshire, Durham, NH, USA
| | - A C Rager
- Catholic University of America, Washington, DC, USA.,NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | | | | | | | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, Toulouse, France
| | - Y Saito
- ISAS/JAXA, Sagamihara, Japan
| | - M Oka
- Space Sciences Laboratory, University of California, Berkeley, CA, USA
| | - R E Ergun
- University of Colorado LASP, Boulder, CO, USA
| | - A Retino
- CNRS/Ecole Polytechnique, Paris, France
| | | | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - F D Wilder
- University of Colorado LASP, Boulder, CO, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, CA, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, CA, USA
| | | | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
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20
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Jian LK, Luhmann JG, Russell CT, Galvin AB. Solar Terrestrial Relations Observatory (STEREO) Observations of Stream Interaction Regions in 2007 - 2016: Relationship with Heliospheric Current Sheets, Solar Cycle Variations, and Dual Observations. Sol Phys 2019; 294:31. [PMID: 31057186 PMCID: PMC6491050 DOI: 10.1007/s11207-019-1416-8] [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] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 02/14/2019] [Indexed: 06/09/2023]
Abstract
We have conducted a survey of 575 slow-to-fast stream interaction regions (SIRs) using Solar Terrestrial Relations Observatory (STEREO) A and B data, analyzing their properties while extending a Level-3 data product through 2016. Among 518 pristine SIRs, 54% are associated with heliospheric current sheet (HCS) crossings, and 34% are without any HCS crossing. The other 12% of the SIRs often occur in association with magnetic sectors shorter than three days. The SIRs with HCS crossings have slightly slower speeds but higher maximum number densities, magnetic-field strengths, dynamic pressures, and total pressures than the SIRs without an HCS. The iron charge state is higher throughout the SIRs with an HCS than the SIRs without an HCS, by about 1/3 charge unit. In contrast with the comparable phases of Solar Cycle 23, slightly more SIRs and higher recurrence rates are observed in the years 2009 - 2016 of Cycle 24, with a lower HCS association rate, possibly attributed to persistent equatorial coronal holes and more pseudo-streamers in this recent cycle. The solar-wind speed, peak magnetic field, and peak pressures of SIRs are all lower in this cycle, but the weakening is less than for the comparable background solar-wind parameters. Before STEREO-B lost contact in October 2014, 151 SIR pairs were observed by the twin spacecraft. Of the dual observations, the maximum speed is the best correlated of the plasma parameters. We have obtained a sample of plasma-parameter differences analogous to those that would be observed by a mission at Lagrange points 4 or 5. By studying several cases with large discrepancies between the dual observations, we investigate the effects of HCS relative location, tilt of stream interface, and small transients on the SIR properties. To resolve the physical reasons for the variability of SIR structures, mesoscale multi-point observations and time-dependent solar-wind modeling are ultimately required.
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Affiliation(s)
- L K Jian
- Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J G Luhmann
- Space Science Laboratory, University of California, Berkeley, CA 94720, USA
| | - C T Russell
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095, USA
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - A B Galvin
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824, USA
- Department of Physics, University of New Hampshire, Durham, NH 03824, USA
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21
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Lognonné P, Banerdt WB, Giardini D, Pike WT, Christensen U, Laudet P, de Raucourt S, Zweifel P, Calcutt S, Bierwirth M, Hurst KJ, Ijpelaan F, Umland JW, Llorca-Cejudo R, Larson SA, Garcia RF, Kedar S, Knapmeyer-Endrun B, Mimoun D, Mocquet A, Panning MP, Weber RC, Sylvestre-Baron A, Pont G, Verdier N, Kerjean L, Facto LJ, Gharakanian V, Feldman JE, Hoffman TL, Klein DB, Klein K, Onufer NP, Paredes-Garcia J, Petkov MP, Willis JR, Smrekar SE, Drilleau M, Gabsi T, Nebut T, Robert O, Tillier S, Moreau C, Parise M, Aveni G, Ben Charef S, Bennour Y, Camus T, Dandonneau PA, Desfoux C, Lecomte B, Pot O, Revuz P, Mance D, tenPierick J, Bowles NE, Charalambous C, Delahunty AK, Hurley J, Irshad R, Liu H, Mukherjee AG, Standley IM, Stott AE, Temple J, Warren T, Eberhardt M, Kramer A, Kühne W, Miettinen EP, Monecke M, Aicardi C, André M, Baroukh J, Borrien A, Bouisset A, Boutte P, Brethomé K, Brysbaert C, Carlier T, Deleuze M, Desmarres JM, Dilhan D, Doucet C, Faye D, Faye-Refalo N, Gonzalez R, Imbert C, Larigauderie C, Locatelli E, Luno L, Meyer JR, Mialhe F, Mouret JM, Nonon M, Pahn Y, Paillet A, Pasquier P, Perez G, Perez R, Perrin L, Pouilloux B, Rosak A, Savin de Larclause I, Sicre J, Sodki M, Toulemont N, Vella B, Yana C, Alibay F, Avalos OM, Balzer MA, Bhandari P, Blanco E, Bone BD, Bousman JC, Bruneau P, Calef FJ, Calvet RJ, D’Agostino SA, de los Santos G, Deen RG, Denise RW, Ervin J, Ferraro NW, Gengl HE, Grinblat F, Hernandez D, Hetzel M, Johnson ME, Khachikyan L, Lin JY, Madzunkov SM, Marshall SL, Mikellides IG, Miller EA, Raff W, Singer JE, Sunday CM, Villalvazo JF, Wallace MC, Banfield D, Rodriguez-Manfredi JA, Russell CT, Trebi-Ollennu A, Maki JN, Beucler E, Böse M, Bonjour C, Berenguer JL, Ceylan S, Clinton J, Conejero V, Daubar I, Dehant V, Delage P, Euchner F, Estève I, Fayon L, Ferraioli L, Johnson CL, Gagnepain-Beyneix J, Golombek M, Khan A, Kawamura T, Kenda B, Labrot P, Murdoch N, Pardo C, Perrin C, Pou L, Sauron A, Savoie D, Stähler S, Stutzmann E, Teanby NA, Tromp J, van Driel M, Wieczorek M, Widmer-Schnidrig R, Wookey J. SEIS: Insight's Seismic Experiment for Internal Structure of Mars. Space Sci Rev 2019; 215:12. [PMID: 30880848 PMCID: PMC6394762 DOI: 10.1007/s11214-018-0574-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 12/29/2018] [Indexed: 05/23/2023]
Abstract
UNLABELLED By the end of 2018, 42 years after the landing of the two Viking seismometers on Mars, InSight will deploy onto Mars' surface the SEIS (Seismic Experiment for Internal Structure) instrument; a six-axes seismometer equipped with both a long-period three-axes Very Broad Band (VBB) instrument and a three-axes short-period (SP) instrument. These six sensors will cover a broad range of the seismic bandwidth, from 0.01 Hz to 50 Hz, with possible extension to longer periods. Data will be transmitted in the form of three continuous VBB components at 2 sample per second (sps), an estimation of the short period energy content from the SP at 1 sps and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams will be augmented by requested event data with sample rates from 20 to 100 sps. SEIS will improve upon the existing resolution of Viking's Mars seismic monitoring by a factor of ∼ 2500 at 1 Hz and ∼ 200 000 at 0.1 Hz. An additional major improvement is that, contrary to Viking, the seismometers will be deployed via a robotic arm directly onto Mars' surface and will be protected against temperature and wind by highly efficient thermal and wind shielding. Based on existing knowledge of Mars, it is reasonable to infer a moment magnitude detection threshold of M w ∼ 3 at 40 ∘ epicentral distance and a potential to detect several tens of quakes and about five impacts per year. In this paper, we first describe the science goals of the experiment and the rationale used to define its requirements. We then provide a detailed description of the hardware, from the sensors to the deployment system and associated performance, including transfer functions of the seismic sensors and temperature sensors. We conclude by describing the experiment ground segment, including data processing services, outreach and education networks and provide a description of the format to be used for future data distribution. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (10.1007/s11214-018-0574-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- P. Lognonné
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - W. B. Banerdt
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - D. Giardini
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - W. T. Pike
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Imperial College London, London, UK
| | - U. Christensen
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - P. Laudet
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - S. de Raucourt
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - P. Zweifel
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - S. Calcutt
- Atmospheric, Oceanic, & Planetary Physics, University of Oxford, Parks Road, Oxford, OX1 3PU UK
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU UK
| | - M. Bierwirth
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - K. J. Hurst
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - F. Ijpelaan
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - J. W. Umland
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - R. Llorca-Cejudo
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - S. A. Larson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - R. F. Garcia
- ISAE-SUPAERO, Toulouse University, 10 Avenue E. Belin, 31400 Toulouse, France
| | - S. Kedar
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - B. Knapmeyer-Endrun
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - D. Mimoun
- ISAE-SUPAERO, Toulouse University, 10 Avenue E. Belin, 31400 Toulouse, France
| | - A. Mocquet
- LPG Nantes, UMR6112, CNRS-Université de Nantes, 2 rue de la Houssinière, BP 92208, 44322 Nantes cedex 3, France
| | - M. P. Panning
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - R. C. Weber
- NASA Marshall Space Flight Center, 320 Sparkman Drive, Huntsville, AL 35805 USA
| | - A. Sylvestre-Baron
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - G. Pont
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - N. Verdier
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - L. Kerjean
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - L. J. Facto
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - V. Gharakanian
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. E. Feldman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - T. L. Hoffman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - D. B. Klein
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - K. Klein
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - N. P. Onufer
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. Paredes-Garcia
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - M. P. Petkov
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. R. Willis
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - S. E. Smrekar
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - M. Drilleau
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - T. Gabsi
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - T. Nebut
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - O. Robert
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - S. Tillier
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - C. Moreau
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - M. Parise
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - G. Aveni
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - S. Ben Charef
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - Y. Bennour
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - T. Camus
- Institut de Recherche en Astrophysique et Planétologie, UMR5277 CNRS - Université Toulouse III Paul Sabatier, 14, avenue Edouard Belin, 31400 Toulouse, France
| | - P. A. Dandonneau
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - C. Desfoux
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - B. Lecomte
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
- Present Address: Institut d’Astrophysique Spatiale, Université Paris-Sud, Bâtiment 121, 91405 Orsay Cedex, France
| | - O. Pot
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
- Present Address: Laboratoire de Mécanique et d’Acoustique, LMA - UMR 7031 AMU - CNRS - Centrale Marseille, 4 impasse Nikola Tesla, CS 40006, 13453 Marseille Cedex 13, France
| | - P. Revuz
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - D. Mance
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - J. tenPierick
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - N. E. Bowles
- Atmospheric, Oceanic, & Planetary Physics, University of Oxford, Parks Road, Oxford, OX1 3PU UK
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU UK
| | - C. Charalambous
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Imperial College London, London, UK
| | - A. K. Delahunty
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Imperial College London, London, UK
- Present Address: Advanced Technology and Research, Arup, 13 Fitzroy Street, London, W1T 4BQ UK
| | - J. Hurley
- Atmospheric, Oceanic, & Planetary Physics, University of Oxford, Parks Road, Oxford, OX1 3PU UK
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU UK
- RAL Space, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, OX11 0QX UK
| | - R. Irshad
- RAL Space, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, OX11 0QX UK
| | - Huafeng Liu
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Imperial College London, London, UK
- Present Address: Center for Gravitational Experiments, Huazhong University of Science and Technology, 1037 Luoyu Rd, Wuhan, 430074 P.R. China
| | - A. G. Mukherjee
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Imperial College London, London, UK
| | | | - A. E. Stott
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Imperial College London, London, UK
| | - J. Temple
- Atmospheric, Oceanic, & Planetary Physics, University of Oxford, Parks Road, Oxford, OX1 3PU UK
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU UK
| | - T. Warren
- Atmospheric, Oceanic, & Planetary Physics, University of Oxford, Parks Road, Oxford, OX1 3PU UK
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU UK
| | - M. Eberhardt
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - A. Kramer
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - W. Kühne
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - E.-P. Miettinen
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - M. Monecke
- Department of Planets and Comets, Max Planck Institute for Solar System Research, Göttingen, Germany
| | - C. Aicardi
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - M. André
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - J. Baroukh
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - A. Borrien
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - A. Bouisset
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - P. Boutte
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - K. Brethomé
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - C. Brysbaert
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - T. Carlier
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - M. Deleuze
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - J. M. Desmarres
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - D. Dilhan
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - C. Doucet
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - D. Faye
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - N. Faye-Refalo
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - R. Gonzalez
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - C. Imbert
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - C. Larigauderie
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - E. Locatelli
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - L. Luno
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - J.-R. Meyer
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - F. Mialhe
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - J. M. Mouret
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - M. Nonon
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - Y. Pahn
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - A. Paillet
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - P. Pasquier
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - G. Perez
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - R. Perez
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - L. Perrin
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - B. Pouilloux
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - A. Rosak
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - I. Savin de Larclause
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - J. Sicre
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - M. Sodki
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - N. Toulemont
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - B. Vella
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - C. Yana
- Centre National d’Etudes Spatiales, 18 av. Edouard Belin, 31401 Toulouse Cedex 9, France
| | - F. Alibay
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - O. M. Avalos
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
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- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - P. Bhandari
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - E. Blanco
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - B. D. Bone
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. C. Bousman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - P. Bruneau
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - F. J. Calef
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - R. J. Calvet
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - S. A. D’Agostino
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - G. de los Santos
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - R. G. Deen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - R. W. Denise
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. Ervin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - N. W. Ferraro
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - H. E. Gengl
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - F. Grinblat
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - D. Hernandez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - M. Hetzel
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - M. E. Johnson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - L. Khachikyan
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. Y. Lin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - S. M. Madzunkov
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - S. L. Marshall
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - I. G. Mikellides
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - E. A. Miller
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - W. Raff
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. E. Singer
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - C. M. Sunday
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. F. Villalvazo
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - M. C. Wallace
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - D. Banfield
- Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY USA
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- Earth, Planetary and Space Sciences, University of California, Los Angeles, Los Angeles, USA
| | - A. Trebi-Ollennu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - J. N. Maki
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - E. Beucler
- LPG Nantes, UMR6112, CNRS-Université de Nantes, 2 rue de la Houssinière, BP 92208, 44322 Nantes cedex 3, France
| | - M. Böse
- Swiss Seismological Service, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - C. Bonjour
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - J. L. Berenguer
- Geoazur, University Cote d’Azur, 250 rue Einstein, 06560 Valbonne, France
| | - S. Ceylan
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - J. Clinton
- Swiss Seismological Service, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - V. Conejero
- Département de Sismologie, Institut de Physique du Globe de Paris-Sorbonne Paris Cité, UMR 7154 CNRS - Université Paris Diderot, 1 Rue Jussieu, Paris Cedex, 75238 France
| | - I. Daubar
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - V. Dehant
- Royal Observatory of Belgium, 3 avenue Circulaire, 1180 Brussels, Belgium
| | - P. Delage
- Laboratoire Navier (CERMES), Ecole des Ponts ParisTech, Marne la Vallée, France
| | - F. Euchner
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - I. Estève
- Institut de Minéralogie et de Physique des Matériaux et de Cosmochimie, Case courrier 115, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - L. Fayon
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - L. Ferraioli
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - C. L. Johnson
- University of British Columbia, Vancouver, BC Canada
- Planetary Science Institute, Tucson, AZ USA
| | - J. Gagnepain-Beyneix
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - M. Golombek
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA
| | - A. Khan
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - T. Kawamura
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - B. Kenda
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - P. Labrot
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - N. Murdoch
- ISAE-SUPAERO, Toulouse University, 10 Avenue E. Belin, 31400 Toulouse, France
| | - C. Pardo
- Département de Sismologie, Institut de Physique du Globe de Paris-Sorbonne Paris Cité, UMR 7154 CNRS - Université Paris Diderot, 1 Rue Jussieu, Paris Cedex, 75238 France
| | - C. Perrin
- Institut de Physique du Globe de Paris-Sorbonne Paris Cité, Université Paris Diderot (UMR 7154 CNRS), Planetology et Space Science Team, 35 Rue Hélène Brion, Paris, 75013 France
| | - L. Pou
- ISAE-SUPAERO, Toulouse University, 10 Avenue E. Belin, 31400 Toulouse, France
| | - A. Sauron
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - D. Savoie
- SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire, 75014 Paris, France
| | - S. Stähler
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - E. Stutzmann
- Département de Sismologie, Institut de Physique du Globe de Paris-Sorbonne Paris Cité, UMR 7154 CNRS - Université Paris Diderot, 1 Rue Jussieu, Paris Cedex, 75238 France
| | - N. A. Teanby
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol, BS8 1RJ UK
| | - J. Tromp
- Department of Geosciences, Princeton University, Guyot Hall, Princeton, NJ 08544 USA
| | - M. van Driel
- Institut of Geophysics, ETHZ, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - M. Wieczorek
- Observatoire de la Côte d’Azur, Boulevard de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France
| | - R. Widmer-Schnidrig
- Black Forest Observatory, Karlsruhe Institute of Technology and Stuttgart University, Heubach 206, 77709 Wolfach, Germany
| | - J. Wookey
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol, BS8 1RJ UK
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22
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Parashar TN, Chasapis A, Bandyopadhyay R, Chhiber R, Matthaeus WH, Maruca B, Shay MA, Burch JL, Moore TE, Giles BL, Gershman DJ, Pollock CJ, Torbert RB, Russell CT, Strangeway RJ, Roytershteyn V. Kinetic Range Spectral Features of Cross Helicity Using the Magnetospheric Multiscale Spacecraft. Phys Rev Lett 2018; 121:265101. [PMID: 30636132 DOI: 10.1103/physrevlett.121.265101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/21/2018] [Indexed: 06/09/2023]
Abstract
We study spectral features of ion velocity and magnetic field correlations in the magnetosheath and in the solar wind using data from the Magnetospheric Multiscale (MMS) spacecraft. High-resolution MMS observations enable the study of the transition of these correlations between their magnetofluid character at larger scales into the subproton kinetic range, previously unstudied in spacecraft data. Cross-helicity, angular alignment, and energy partitioning is examined over a suitable range of scales, employing measurements based on the Taylor frozen-in approximation as well as direct two-spacecraft correlation measurements. The results demonstrate signatures of alignment at large scales. As kinetic scales are approached, the alignment between v and b is destroyed by demagnetization of protons.
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Affiliation(s)
- Tulasi N Parashar
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Alexandros Chasapis
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Riddhi Bandyopadhyay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Rohit Chhiber
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - W H Matthaeus
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - B Maruca
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - M A Shay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - J L Burch
- Southwest Research Institute, San Antonio 78238-5166, Texas, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - C J Pollock
- Denali Scientific, Fairbanks 99709, Alaska, USA
| | - R B Torbert
- University of New Hampshire, Durham 03824, New Hampshire, USA
| | - C T Russell
- University of California, Los Angeles 90095-1567, California, USA
| | - R J Strangeway
- University of California, Los Angeles 90095-1567, California, USA
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23
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Torbert RB, Burch JL, Phan TD, Hesse M, Argall MR, Shuster J, Ergun RE, Alm L, Nakamura R, Genestreti KJ, Gershman DJ, Paterson WR, Turner DL, Cohen I, Giles BL, Pollock CJ, Wang S, Chen LJ, Stawarz JE, Eastwood JP, Hwang KJ, Farrugia C, Dors I, Vaith H, Mouikis C, Ardakani A, Mauk BH, Fuselier SA, Russell CT, Strangeway RJ, Moore TE, Drake JF, Shay MA, Khotyaintsev YV, Lindqvist PA, Baumjohann W, Wilder FD, Ahmadi N, Dorelli JC, Avanov LA, Oka M, Baker DN, Fennell JF, Blake JB, Jaynes AN, Le Contel O, Petrinec SM, Lavraud B, Saito Y. Electron-scale dynamics of the diffusion region during symmetric magnetic reconnection in space. Science 2018; 362:1391-1395. [PMID: 30442767 DOI: 10.1126/science.aat2998] [Citation(s) in RCA: 158] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 11/06/2018] [Indexed: 11/02/2022]
Abstract
Magnetic reconnection is an energy conversion process that occurs in many astrophysical contexts including Earth's magnetosphere, where the process can be investigated in situ by spacecraft. On 11 July 2017, the four Magnetospheric Multiscale spacecraft encountered a reconnection site in Earth's magnetotail, where reconnection involves symmetric inflow conditions. The electron-scale plasma measurements revealed (i) super-Alfvénic electron jets reaching 15,000 kilometers per second; (ii) electron meandering motion and acceleration by the electric field, producing multiple crescent-shaped structures in the velocity distributions; and (iii) the spatial dimensions of the electron diffusion region with an aspect ratio of 0.1 to 0.2, consistent with fast reconnection. The well-structured multiple layers of electron populations indicate that the dominant electron dynamics are mostly laminar, despite the presence of turbulence near the reconnection site.
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Affiliation(s)
- R B Torbert
- University of New Hampshire, Durham, NH, USA. .,Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - T D Phan
- University of California, Berkeley, CA, USA
| | - M Hesse
- Southwest Research Institute (SwRI), San Antonio, TX, USA.,University of Bergen, Bergen, Norway
| | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - J Shuster
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - R E Ergun
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - L Alm
- Swedish Institute of Space Physics, Uppsala, Sweden
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - K J Genestreti
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - D L Turner
- Aerospace Corporation, El Segundo, CA, USA
| | - I Cohen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - S Wang
- University of Maryland, College Park, MD, USA
| | - L-J Chen
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,University of Maryland, College Park, MD, USA
| | - J E Stawarz
- Blackett Laboratory, Imperial College London, London, UK
| | - J P Eastwood
- Blackett Laboratory, Imperial College London, London, UK
| | - K J Hwang
- Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - C Farrugia
- University of New Hampshire, Durham, NH, USA
| | - I Dors
- University of New Hampshire, Durham, NH, USA
| | - H Vaith
- University of New Hampshire, Durham, NH, USA
| | - C Mouikis
- University of New Hampshire, Durham, NH, USA
| | - A Ardakani
- University of New Hampshire, Durham, NH, USA
| | - B H Mauk
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - S A Fuselier
- Southwest Research Institute (SwRI), San Antonio, TX, USA.,University of Texas, San Antonio, TX, USA
| | - C T Russell
- University of California, Los Angeles, CA, USA
| | | | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J F Drake
- University of Maryland, College Park, MD, USA
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | | | | | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - F D Wilder
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - N Ahmadi
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - L A Avanov
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - M Oka
- University of California, Berkeley, CA, USA
| | - D N Baker
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | | | - J B Blake
- Aerospace Corporation, El Segundo, CA, USA
| | | | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | - S M Petrinec
- Lockheed Martin Advanced Technology Center, Palo Alto, CA, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, CNRS, Centre National d'Etudes Spatiales, Université de Toulouse, Toulouse, France
| | - Y Saito
- Institute for Space and Astronautical Sciences, Sagamihara, Japan
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24
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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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25
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Turner DL, Wilson LB, Liu TZ, Cohen IJ, Schwartz SJ, Osmane A, Fennell JF, Clemmons JH, Blake JB, Westlake J, Mauk BH, Jaynes AN, Leonard T, Baker DN, Strangeway RJ, Russell CT, Gershman DJ, Avanov L, Giles BL, Torbert RB, Broll J, Gomez RG, Fuselier SA, Burch JL. Autogenous and efficient acceleration of energetic ions upstream of Earth's bow shock. Nature 2018; 561:206-210. [PMID: 30209369 DOI: 10.1038/s41586-018-0472-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/06/2018] [Indexed: 11/09/2022]
Abstract
Earth and its magnetosphere are immersed in the supersonic flow of the solar-wind plasma that fills interplanetary space. As the solar wind slows and deflects to flow around Earth, or any other obstacle, a 'bow shock' forms within the flow. Under almost all solar-wind conditions, planetary bow shocks such as Earth's are collisionless, supercritical shocks, meaning that they reflect and accelerate a fraction of the incident solar-wind ions as an energy dissipation mechanism1,2, which results in the formation of a region called the ion foreshock3. In the foreshock, large-scale, transient phenomena can develop, such as 'hot flow anomalies'4-9, which are concentrations of shock-reflected, suprathermal ions that are channelled and accumulated along certain structures in the upstream magnetic field. Hot flow anomalies evolve explosively, often resulting in the formation of new shocks along their upstream edges5,10, and potentially contribute to particle acceleration11-13, but there have hitherto been no observations to constrain this acceleration or to confirm the underlying mechanism. Here we report observations of a hot flow anomaly accelerating solar-wind ions from roughly 1-10 kiloelectronvolts up to almost 1,000 kiloelectronvolts. The acceleration mechanism depends on the mass and charge state of the ions and is consistent with first-order Fermi acceleration14,15. The acceleration that we observe results from only the interaction of Earth's bow shock with the solar wind, but produces a much, much larger number of energetic particles compared to what would typically be produced in the foreshock from acceleration at the bow shock. Such autogenous and efficient acceleration at quasi-parallel bow shocks (the normal direction of which are within about 45 degrees of the interplanetary magnetic field direction) provides a potential solution to Fermi's 'injection problem', which requires an as-yet-unexplained seed population of energetic particles, and implies that foreshock transients may be important in the generation of cosmic rays at astrophysical shocks throughout the cosmos.
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Affiliation(s)
- D L Turner
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA.
| | - L B Wilson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T Z Liu
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - I J Cohen
- Applied Physics Laboratory, Laurel, MD, USA
| | | | - A Osmane
- School of Electrical Engineering, Aalto University, Espoo, Finland.,Rudolf Peierls Centre of Theoretical Physics, University of Oxford, Oxford, UK
| | - J F Fennell
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - J H Clemmons
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - J B Blake
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - J Westlake
- Applied Physics Laboratory, Laurel, MD, USA
| | - B H Mauk
- Applied Physics Laboratory, Laurel, MD, USA
| | - A N Jaynes
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA, USA
| | - T Leonard
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - D N Baker
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - R J Strangeway
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - C T Russell
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - L Avanov
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - R B Torbert
- Institute For the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, USA.,Southwest Research Institute, San Antonio, TX, USA
| | - J Broll
- Southwest Research Institute, San Antonio, TX, USA.,Departoment of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
| | - R G Gomez
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, TX, USA.,Departoment of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
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Kitamura N, Kitahara M, Shoji M, Miyoshi Y, Hasegawa H, Nakamura S, Katoh Y, Saito Y, Yokota S, Gershman DJ, Vinas AF, Giles BL, Moore TE, Paterson WR, Pollock CJ, Russell CT, Strangeway RJ, Fuselier SA, Burch JL. Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma. Science 2018; 361:1000-1003. [PMID: 30190400 DOI: 10.1126/science.aap8730] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 07/04/2018] [Indexed: 11/02/2022]
Abstract
Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth's magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He+ to energies up to ~2 kilo-electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.
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Affiliation(s)
- N Kitamura
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan. .,Department of Earth and Planetary Science, Graduate School of Science, the University of Tokyo, Tokyo, Japan
| | - M Kitahara
- Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Japan
| | - M Shoji
- Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Nagoya, Japan
| | - Y Miyoshi
- Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Nagoya, Japan
| | - H Hasegawa
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - S Nakamura
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Uji, Japan
| | - Y Katoh
- Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Japan
| | - Y Saito
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - S Yokota
- Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - A F Vinas
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Department of Physics, American University, Washington, DC, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | - C T Russell
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, USA
| | - R J Strangeway
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, TX, USA.,University of Texas at San Antonio, San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
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27
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Eastwood JP, Mistry R, Phan TD, Schwartz SJ, Ergun RE, Drake JF, Øieroset M, Stawarz JE, Goldman MV, Haggerty C, Shay MA, Burch JL, Gershman DJ, Giles BL, Lindqvist PA, Torbert RB, Strangeway RJ, Russell CT. Guide Field Reconnection: Exhaust Structure and Heating. Geophys Res Lett 2018; 45:4569-4577. [PMID: 31031447 PMCID: PMC6473590 DOI: 10.1029/2018gl077670] [Citation(s) in RCA: 1] [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: 02/23/2018] [Revised: 04/11/2018] [Accepted: 04/14/2018] [Indexed: 06/09/2023]
Abstract
Magnetospheric Multiscale observations are used to probe the structure and temperature profile of a guide field reconnection exhaust ~100 ion inertial lengths downstream from the X-line in the Earth's magnetosheath. Asymmetric Hall electric and magnetic field signatures were detected, together with a density cavity confined near 1 edge of the exhaust and containing electron flow toward the X-line. Electron holes were also detected both on the cavity edge and at the Hall magnetic field reversal. Predominantly parallel ion and electron heating was observed in the main exhaust, but within the cavity, electron cooling and enhanced parallel ion heating were found. This is explained in terms of the parallel electric field, which inhibits electron mixing within the cavity on newly reconnected field lines but accelerates ions. Consequently, guide field reconnection causes inhomogeneous changes in ion and electron temperature across the exhaust.
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Affiliation(s)
| | - R. Mistry
- The Blackett LaboratoryImperial College LondonLondonUK
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - S. J. Schwartz
- The Blackett LaboratoryImperial College LondonLondonUK
- LASP/Department of Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - R. E. Ergun
- LASP/Department of Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - J. F. Drake
- Department of Physics and Institute for Physical Science and TechnologyUniversity of MarylandCollege ParkMDUSA
| | - M. Øieroset
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - J. E. Stawarz
- The Blackett LaboratoryImperial College LondonLondonUK
| | - M. V. Goldman
- Department of PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - C. Haggerty
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
- Now at The Department of Astronomy and AstrophysicsUniversity of ChicagoChicagoILUSA
| | - M. A. Shay
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - D. J. Gershman
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - P. A. Lindqvist
- Department of Space and Plasma PhysicsRoyal Institute of TechnologyStockholmSweden
| | - R. B. Torbert
- Now at The Department of Astronomy and AstrophysicsUniversity of ChicagoChicagoILUSA
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
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28
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Burch JL, Webster JM, Genestreti KJ, Torbert RB, Giles BL, Fuselier SA, Dorelli JC, Rager AC, Phan TD, Allen RC, Chen L, Wang S, Le Contel O, Russell CT, Strangeway RJ, Ergun RE, Jaynes AN, Lindqvist P, Graham DB, Wilder FD, Hwang K, Goldstein J. Wave Phenomena and Beam-Plasma Interactions at the Magnetopause Reconnection Region. J Geophys Res Space Phys 2018; 123:1118-1133. [PMID: 29938153 PMCID: PMC5993346 DOI: 10.1002/2017ja024789] [Citation(s) in RCA: 1] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 12/28/2017] [Accepted: 01/10/2018] [Indexed: 06/08/2023]
Abstract
This paper reports on Magnetospheric Multiscale observations of whistler mode chorus and higher-frequency electrostatic waves near and within a reconnection diffusion region on 23 November 2016. The diffusion region is bounded by crescent-shaped electron distributions and associated dissipation just upstream of the X-line and by magnetic field-aligned currents and electric fields leading to dissipation near the electron stagnation point. Measurements were made southward of the X-line as determined by southward directed ion and electron jets. We show that electrostatic wave generation is due to magnetosheath electron beams formed by the electron jets as they interact with a cold background plasma and more energetic population of magnetospheric electrons. On the magnetosphere side of the X-line the electron beams are accompanied by a strong perpendicular electron temperature anisotropy, which is shown to be the source of an observed rising-tone whistler mode chorus event. We show that the apex of the chorus event and the onset of electrostatic waves coincide with the opening of magnetic field lines at the electron stagnation point.
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Affiliation(s)
- J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - J. M. Webster
- Department of Physics and AstronomyRice UniversityHoustonTXUSA
| | | | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- Department of PhysicsUniversity of New HampshireDurhamNHUSA
| | - B. L. Giles
- NASA, Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - A. C. Rager
- NASA, Goddard Space Flight CenterGreenbeltMDUSA
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - R. C. Allen
- Applied Physics LaboratoryThe Johns Hopkins UniversityLaurelMDUSA
| | - L.‐J. Chen
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - S. Wang
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - O. Le Contel
- Laboratoire de Physique des PlasmasCNRS, Ecole Polytechnique, UPMC University Paris 06, Université Paris‐Sud, Observatoire de ParisParisFrance
| | - C. T. Russell
- Earth and Planetary SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Earth and Planetary SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. E. Ergun
- LASPUniversity of Colorado BoulderBoulderCOUSA
| | - A. N. Jaynes
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | | | | | | | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
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29
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Rager AC, Dorelli JC, Gershman DJ, Uritsky V, Avanov LA, Torbert RB, Burch JL, Ergun RE, Egedal J, Schiff C, Shuster JR, Giles BL, Paterson WR, Pollock CJ, Strangeway RJ, Russell CT, Lavraud B, Coffey VN, Saito Y. Electron Crescent Distributions as a Manifestation of Diamagnetic Drift in an Electron-Scale Current Sheet: Magnetospheric Multiscale Observations Using New 7.5 ms Fast Plasma Investigation Moments. Geophys Res Lett 2018; 45:578-584. [PMID: 29576666 PMCID: PMC5856066 DOI: 10.1002/2017gl076260] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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: 11/02/2017] [Revised: 12/25/2017] [Accepted: 01/07/2018] [Indexed: 06/08/2023]
Abstract
We report Magnetospheric Multiscale observations of electron pressure gradient electric fields near a magnetic reconnection diffusion region using a new technique for extracting 7.5 ms electron moments from the Fast Plasma Investigation. We find that the deviation of the perpendicular electron bulk velocity from E × B drift in the interval where the out-of-plane current density is increasing can be explained by the diamagnetic drift. In the interval where the out-of-plane current is transitioning to in-plane current, the electron momentum equation is not satisfied at 7.5 ms resolution.
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Affiliation(s)
- A. C. Rager
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - V. Uritsky
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - L. A. Avanov
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - R. B. Torbert
- Department of PhysicsUniversity of New HampshireDurhamNHUSA
- Southwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - R. E. Ergun
- Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - J. Egedal
- Department of PhysicsUniversity of WisconsinMadisonWIUSA
| | - C. Schiff
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - J. R. Shuster
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - R. J. Strangeway
- Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - C. T. Russell
- Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - B. Lavraud
- Research Institute in Astrophysics and PlanetologyToulouseFrance
| | - V. N. Coffey
- NASA Marshall Space Flight CenterHuntsvilleALUSA
| | - Y. Saito
- Institute for Space and Astronautical ScienceSagamiharaJapan
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30
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Servidio S, Chasapis A, Matthaeus WH, Perrone D, Valentini F, Parashar TN, Veltri P, Gershman D, Russell CT, Giles B, Fuselier SA, Phan TD, Burch J. Magnetospheric Multiscale Observation of Plasma Velocity-Space Cascade: Hermite Representation and Theory. Phys Rev Lett 2017; 119:205101. [PMID: 29219385 DOI: 10.1103/physrevlett.119.205101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Indexed: 06/07/2023]
Abstract
Plasma turbulence is investigated using unprecedented high-resolution ion velocity distribution measurements by the Magnetospheric Multiscale mission (MMS) in the Earth's magnetosheath. This novel observation of a highly structured particle distribution suggests a cascadelike process in velocity space. Complex velocity space structure is investigated using a three-dimensional Hermite transform, revealing, for the first time in observational data, a power-law distribution of moments. In analogy to hydrodynamics, a Kolmogorov approach leads directly to a range of predictions for this phase-space transport. The scaling theory is found to be in agreement with observations. The combined use of state-of-the-art MMS data sets, novel implementation of a Hermite transform method, and scaling theory of the velocity cascade opens new pathways to the understanding of plasma turbulence and the crucial velocity space features that lead to dissipation in plasmas.
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Affiliation(s)
- S Servidio
- Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy
| | - A Chasapis
- Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - W H Matthaeus
- Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - D Perrone
- European Space Agency, ESAC, 28692 Madrid, Spain
| | - F Valentini
- Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy
| | - T N Parashar
- Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - P Veltri
- Dipartimento di Fisica, Università della Calabria, I-87036 Cosenza, Italy
| | - D Gershman
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C T Russell
- University of California at Los Angeles, Los Angeles, California 90095, USA
| | - B Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, Texas 78238, USA
- University of Texas at San Antonio, San Antonio, Texas 78249, USA
| | - T D Phan
- University of California, Berkeley, California 94720, USA
| | - J Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
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31
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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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32
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De Sanctis MC, Ammannito E, McSween HY, Raponi A, Marchi S, Capaccioni F, Capria MT, Carrozzo FG, Ciarniello M, Fonte S, Formisano M, Frigeri A, Giardino M, Longobardo A, Magni G, McFadden LA, Palomba E, Pieters CM, Tosi F, Zambon F, Raymond CA, Russell CT. Localized aliphatic organic material on the surface of Ceres. Science 2017; 355:719-722. [PMID: 28209893 DOI: 10.1126/science.aaj2305] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 01/17/2017] [Indexed: 11/02/2022]
Abstract
Organic compounds occur in some chondritic meteorites, and their signatures on solar system bodies have been sought for decades. Spectral signatures of organics have not been unambiguously identified on the surfaces of asteroids, whereas they have been detected on cometary nuclei. Data returned by the Visible and InfraRed Mapping Spectrometer on board the Dawn spacecraft show a clear detection of an organic absorption feature at 3.4 micrometers on dwarf planet Ceres. This signature is characteristic of aliphatic organic matter and is mainly localized on a broad region of ~1000 square kilometers close to the ~50-kilometer Ernutet crater. The combined presence on Ceres of ammonia-bearing hydrated minerals, water ice, carbonates, salts, and organic material indicates a very complex chemical environment, suggesting favorable environments to prebiotic chemistry.
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Affiliation(s)
- M C De Sanctis
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - E Ammannito
- Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA.,Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - H Y McSween
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996-1410, USA
| | - A Raponi
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA.,Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - F Capaccioni
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M T Capria
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - F G Carrozzo
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M Ciarniello
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - S Fonte
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M Formisano
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - A Frigeri
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M Giardino
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - A Longobardo
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - G Magni
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - L A McFadden
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - E Palomba
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - C M Pieters
- Brown University, Department of Earth, Environmental, and Planetary Sciences, Providence, RI 02912, USA
| | - F Tosi
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - F Zambon
- Istituto di Astrofisica e Planetologia Spaziali-Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - C T Russell
- Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
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33
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Cattell C, Breneman A, Colpitts C, Dombeck J, Thaller S, Tian S, Wygant J, Fennell J, Hudson MK, Ergun R, Russell CT, Torbert R, Lindqvist P, Burch J. Dayside response of the magnetosphere to a small shock compression: Van Allen Probes, Magnetospheric MultiScale, and GOES-13. Geophys Res Lett 2017; 44:8712-8720. [PMID: 29104327 PMCID: PMC5661744 DOI: 10.1002/2017gl074895] [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: 07/10/2017] [Revised: 08/04/2017] [Accepted: 08/08/2017] [Indexed: 06/07/2023]
Abstract
Observations from Magnetospheric MultiScale (~8 Re) and Van Allen Probes (~5 and 4 Re) show that the initial dayside response to a small interplanetary shock is a double-peaked dawnward electric field, which is distinctly different from the usual bipolar (dawnward and then duskward) signature reported for large shocks. The associated E × B flow is radially inward. The shock compressed the magnetopause to inside 8 Re, as observed by Magnetospheric MultiScale (MMS), with a speed that is comparable to the E × B flow. The magnetopause speed and the E × B speeds were significantly less than the propagation speed of the pulse from MMS to the Van Allen Probes and GOES-13, which is consistent with the MHD fast mode. There were increased fluxes of energetic electrons up to several MeV. Signatures of drift echoes and response to ULF waves also were seen. These observations demonstrate that even very weak shocks can have significant impact on the radiation belts.
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Affiliation(s)
- C. Cattell
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - A. Breneman
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - C. Colpitts
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - J. Dombeck
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - S. Thaller
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - S. Tian
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - J. Wygant
- School of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
| | - J. Fennell
- Aerospace CorporationEl SegundoCaliforniaUSA
| | - M. K. Hudson
- Department of Physics and AstronomyDartmouth CollegeHanoverNew HampshireUSA
| | - Robert Ergun
- LASPUniversity of Colorado BoulderBoulderColoradoUSA
| | | | - Roy Torbert
- EOSUniversity of New HampshireDurhamNew HampshireUSA
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34
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Zhou M, Berchem J, Walker RJ, El-Alaoui M, Deng X, Cazzola E, Lapenta G, Goldstein ML, Paterson WR, Pang Y, Ergun RE, Lavraud B, Liang H, Russell CT, Strangeway RJ, Zhao C, Giles BL, Pollock CJ, Lindqvist PA, Marklund G, Wilder FD, Khotyaintsev YV, Torbert RB, Burch JL. Coalescence of Macroscopic Flux Ropes at the Subsolar Magnetopause: Magnetospheric Multiscale Observations. Phys Rev Lett 2017; 119:055101. [PMID: 28949734 DOI: 10.1103/physrevlett.119.055101] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Indexed: 06/07/2023]
Abstract
We report unambiguous in situ observation of the coalescence of macroscopic flux ropes by the magnetospheric multiscale (MMS) mission. Two coalescing flux ropes with sizes of ∼1 R_{E} were identified at the subsolar magnetopause by the occurrence of an asymmetric quadrupolar signature in the normal component of the magnetic field measured by the MMS spacecraft. An electron diffusion region (EDR) with a width of four local electron inertial lengths was embedded within the merging current sheet. The EDR was characterized by an intense parallel electric field, significant energy dissipation, and suprathermal electrons. Although the electrons were organized by a large guide field, the small observed electron pressure nongyrotropy may be sufficient to support a significant fraction of the parallel electric field within the EDR. Since the flux ropes are observed in the exhaust region, we suggest that secondary EDRs are formed further downstream of the primary reconnection line between the magnetosheath and magnetospheric fields.
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Affiliation(s)
- M Zhou
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - J Berchem
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - R J Walker
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - M El-Alaoui
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - X Deng
- Nanchang University, Nanchang 330031, People's Republic of China
| | - E Cazzola
- Centre for Plasma Astrophysics, Department of Mathematics, Katholieke Universiteit, Leuven 3001, Belgium
| | - G Lapenta
- Centre for Plasma Astrophysics, Department of Mathematics, Katholieke Universiteit, Leuven 3001, Belgium
| | - M L Goldstein
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
- Space Science Institute, Boulder 80301, Colorado, USA
| | - W R Paterson
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - Y Pang
- Nanchang University, Nanchang 330031, People's Republic of China
| | - R E Ergun
- University of Colorado LASP, Boulder 80303, Colorado, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, UPS, CNES, Toulouse 31028, France
| | - H Liang
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - C T Russell
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - R J Strangeway
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - C Zhao
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - P-A Lindqvist
- Royal Institute of Technology, Stockholm SE-11428, Sweden
| | - G Marklund
- Royal Institute of Technology, Stockholm SE-11428, Sweden
| | - F D Wilder
- University of Colorado LASP, Boulder 80303, Colorado, USA
| | | | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - J L Burch
- Southwest Research Institute, San Antonio Texas 78238, USA
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35
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Sizemore HG, Platz T, Schorghofer N, Prettyman TH, De Sanctis MC, Crown DA, Schmedemann N, Neesemann A, Kneissl T, Marchi S, Schenk PM, Bland MT, Schmidt BE, Hughson KHG, Tosi F, Zambon F, Mest SC, Yingst RA, Williams DA, Russell CT, Raymond CA. Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution. Geophys Res Lett 2017; 44:6570-6578. [PMID: 28989206 PMCID: PMC5606497 DOI: 10.1002/2017gl073970] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [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: 04/26/2017] [Revised: 06/19/2017] [Accepted: 06/22/2017] [Indexed: 06/07/2023]
Abstract
Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.
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Affiliation(s)
| | - T. Platz
- Max Planck Institute for Solar System ResearchGöttingenGermany
| | | | | | | | | | - N. Schmedemann
- Department of Earth SciencesFreie Universität BerlinBerlinGermany
| | - A. Neesemann
- Department of Earth SciencesFreie Universität BerlinBerlinGermany
| | - T. Kneissl
- Department of Earth SciencesFreie Universität BerlinBerlinGermany
| | - S. Marchi
- Southwest Research InstituteBoulderColoradoUSA
| | | | - M. T. Bland
- USGS Astrogeology Science CenterFlagstaffArizonaUSA
| | - B. E. Schmidt
- Department of Planetary and Space PhysicsGeorgia Institute of TechnologyAtlantaGeorgiaUSA
| | - K. H. G. Hughson
- Department of Earth, Planetary, and Space SciencesUniversity of California Los AngelesLos AngelesCaliforniaUSA
| | - F. Tosi
- Istituto di Astrofisica e Planetologia Spaziali, INAFRomeItaly
| | - F. Zambon
- Istituto di Astrofisica e Planetologia Spaziali, INAFRomeItaly
| | - S. C. Mest
- Planetary Science InstituteTucsonArizonaUSA
| | | | - D. A. Williams
- School of Earth and Space SciencesArizona State UniversityTempeArizonaUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of California Los AngelesLos AngelesCaliforniaUSA
| | - C. A. Raymond
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCaliforniaUSA
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36
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Graham DB, Khotyaintsev YV, Vaivads A, Norgren C, André M, Webster JM, Burch JL, Lindqvist PA, Ergun RE, Torbert RB, Paterson WR, Gershman DJ, Giles BL, Magnes W, Russell CT. Instability of Agyrotropic Electron Beams near the Electron Diffusion Region. Phys Rev Lett 2017; 119:025101. [PMID: 28753352 DOI: 10.1103/physrevlett.119.025101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Indexed: 06/07/2023]
Abstract
During a magnetopause crossing the Magnetospheric Multiscale spacecraft encountered an electron diffusion region (EDR) of asymmetric reconnection. The EDR is characterized by agyrotropic beam and crescent electron distributions perpendicular to the magnetic field. Intense upper-hybrid (UH) waves are found at the boundary between the EDR and magnetosheath inflow region. The UH waves are generated by the agyrotropic electron beams. The UH waves are sufficiently large to contribute to electron diffusion and scattering, and are a potential source of radio emission near the EDR. These results provide observational evidence of wave-particle interactions at an EDR, and suggest that waves play an important role in determining the electron dynamics.
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Affiliation(s)
- D B Graham
- Swedish Institute of Space Physics, Uppsala SE-75121, Sweden
| | | | - A Vaivads
- Swedish Institute of Space Physics, Uppsala SE-75121, Sweden
| | - C Norgren
- Swedish Institute of Space Physics, Uppsala SE-75121, Sweden
- Department of Physics and Astronomy, Uppsala University, Uppsala SE-75121, Sweden
| | - M André
- Swedish Institute of Space Physics, Uppsala SE-75121, Sweden
| | - J M Webster
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - P-A Lindqvist
- Space and Plasma Physics, School of Electrical Engineering, KTH Royal Institute of Technology, Stockholm SE-11428, Sweden
| | - R E Ergun
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - R B Torbert
- Space Science Center, 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
- Department of Astronomy, University of Maryland, College Park, Maryland 20742, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - C T Russell
- Department of Earth and Space Sciences, University of California, Los Angeles, California 90095, USA
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37
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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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38
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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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39
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Russell CT, Raymond CA, Ammannito E, Buczkowski DL, De Sanctis MC, Hiesinger H, Jaumann R, Konopliv AS, McSween HY, Nathues A, Park RS, Pieters CM, Prettyman TH, McCord TB, McFadden LA, Mottola S, Zuber MT, Joy SP, Polanskey C, Rayman MD, Castillo-Rogez JC, Chi PJ, Combe JP, Ermakov A, Fu RR, Hoffmann M, Jia YD, King SD, Lawrence DJ, Li JY, Marchi S, Preusker F, Roatsch T, Ruesch O, Schenk P, Villarreal MN, Yamashita N. Dawn arrives at Ceres: Exploration of a small, volatile-rich world. Science 2017; 353:1008-1010. [PMID: 27701107 DOI: 10.1126/science.aaf4219] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 07/13/2016] [Indexed: 11/02/2022]
Abstract
On 6 March 2015, Dawn arrived at Ceres to find a dark, desiccated surface punctuated by small, bright areas. Parts of Ceres' surface are heavily cratered, but the largest expected craters are absent. Ceres appears gravitationally relaxed at only the longest wavelengths, implying a mechanically strong lithosphere with a weaker deep interior. Ceres' dry exterior displays hydroxylated silicates, including ammoniated clays of endogenous origin. The possibility of abundant volatiles at depth is supported by geomorphologic features such as flat crater floors with pits, lobate flows of materials, and a singular mountain that appears to be an extrusive cryovolcanic dome. On one occasion, Ceres temporarily interacted with the solar wind, producing a bow shock accelerating electrons to energies of tens of kilovolts.
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Affiliation(s)
- C T Russell
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA.
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - E Ammannito
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - D L Buczkowski
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA
| | - M C De Sanctis
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - H Hiesinger
- Institut für Planetologie, 48149 Münster, Germany
| | - R Jaumann
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - A S Konopliv
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - H Y McSween
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996-1410, USA
| | - A Nathues
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - R S Park
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - C M Pieters
- Brown University, Department of Earth, Environmental, and Planetary Sciences, Providence, RI 02912, USA
| | | | - T B McCord
- The Bear Fight Institute, Winthrop, WA 98862, USA
| | - L A McFadden
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - S Mottola
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - M T Zuber
- Massachussetts Institute of Technology, Cambridge, MA 02139, USA
| | - S P Joy
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - C Polanskey
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - M D Rayman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - J C Castillo-Rogez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - P J Chi
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - J P Combe
- The Bear Fight Institute, Winthrop, WA 98862, USA
| | - A Ermakov
- Massachussetts Institute of Technology, Cambridge, MA 02139, USA
| | - R R Fu
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10968, USA
| | - M Hoffmann
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Y D Jia
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - S D King
- Virginia Tech, Geosciences, Blacksburg, VA 24061, USA
| | - D J Lawrence
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA
| | - J-Y Li
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA
| | - F Preusker
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - T Roatsch
- Deutsches Zentrum fur Luft-und Raumfahrt, Institute of Planetary Research, 12489 Berlin, Germany
| | - O Ruesch
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - P Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - M N Villarreal
- Earth Planetary and Space Sciences, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - N Yamashita
- Planetary Science Institute, Tucson, AZ 85719, USA
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40
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Prettyman TH, Yamashita N, Toplis MJ, McSween HY, Schörghofer N, Marchi S, Feldman WC, Castillo-Rogez J, Forni O, Lawrence DJ, Ammannito E, Ehlmann BL, Sizemore HG, Joy SP, Polanskey CA, Rayman MD, Raymond CA, Russell CT. Extensive water ice within Ceres' aqueously altered regolith: Evidence from nuclear spectroscopy. Science 2016; 355:55-59. [PMID: 27980087 DOI: 10.1126/science.aah6765] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 11/23/2016] [Indexed: 11/03/2022]
Abstract
The surface elemental composition of dwarf planet Ceres constrains its regolith ice content, aqueous alteration processes, and interior evolution. Using nuclear spectroscopy data acquired by NASA's Dawn mission, we determined the concentrations of elemental hydrogen, iron, and potassium on Ceres. The data show that surface materials were processed by the action of water within the interior. The non-icy portion of Ceres' carbon-bearing regolith contains similar amounts of hydrogen to those present in aqueously altered carbonaceous chondrites; however, the concentration of iron on Ceres is lower than in the aforementioned chondrites. This allows for the possibility that Ceres experienced modest ice-rock fractionation, resulting in differences between surface and bulk composition. At mid-to-high latitudes, the regolith contains high concentrations of hydrogen, consistent with broad expanses of water ice, confirming theoretical predictions that ice can survive for billions of years just beneath the surface.
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Affiliation(s)
- T H Prettyman
- Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395, USA.
| | - N Yamashita
- Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395, USA
| | - M J Toplis
- Institut de Recherche d'Astrophysique et Planétologie, CNRS, Université Paul Sabatier, Toulouse 31400, France
| | - H Y McSween
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996-1410, USA
| | - N Schörghofer
- University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA
| | - W C Feldman
- Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395, USA
| | - J Castillo-Rogez
- Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - O Forni
- Institut de Recherche d'Astrophysique et Planétologie, CNRS, Université Paul Sabatier, Toulouse 31400, France
| | - D J Lawrence
- Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E Ammannito
- Earth Planetary and Space Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1567, USA
| | - B L Ehlmann
- Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, CA 91109-8099, USA.,Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - H G Sizemore
- Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395, USA
| | - S P Joy
- Earth Planetary and Space Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1567, USA
| | - C A Polanskey
- Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - M D Rayman
- Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - C A Raymond
- Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, CA 91109-8099, USA
| | - C T Russell
- Earth Planetary and Space Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1567, USA
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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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42
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Hiesinger H, Marchi S, Schmedemann N, Schenk P, Pasckert JH, Neesemann A, O'Brien DP, Kneissl T, Ermakov AI, Fu RR, Bland MT, Nathues A, Platz T, Williams DA, Jaumann R, Castillo-Rogez JC, Ruesch O, Schmidt B, Park RS, Preusker F, Buczkowski DL, Russell CT, Raymond CA. Cratering on Ceres: Implications for its crust and evolution. Science 2016; 353:353/6303/aaf4759. [PMID: 27701089 DOI: 10.1126/science.aaf4759] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 07/29/2016] [Indexed: 11/02/2022]
Abstract
Thermochemical models have predicted that Ceres, is to some extent, differentiated and should have an icy crust with few or no impact craters. We present observations by the Dawn spacecraft that reveal a heavily cratered surface, a heterogeneous crater distribution, and an apparent absence of large craters. The morphology of some impact craters is consistent with ice in the subsurface, which might have favored relaxation, yet large unrelaxed craters are also present. Numerous craters exhibit polygonal shapes, terraces, flowlike features, slumping, smooth deposits, and bright spots. Crater morphology and simple-to-complex crater transition diameters indicate that the crust of Ceres is neither purely icy nor rocky. By dating a smooth region associated with the Kerwan crater, we determined absolute model ages (AMAs) of 550 million and 720 million years, depending on the applied chronology model.
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Affiliation(s)
- H Hiesinger
- Institut für Planetologie, Westfälische Wilhelms-Universität, Münster, Germany.
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA
| | - N Schmedemann
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - P Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - J H Pasckert
- Institut für Planetologie, Westfälische Wilhelms-Universität, Münster, Germany
| | - A Neesemann
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - D P O'Brien
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - T Kneissl
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - A I Ermakov
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - R R Fu
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - M T Bland
- U.S. Geological Survey, Astrogeology Science Center, Flagstaff, AZ 86001, USA
| | - A Nathues
- Max-Planck Institute for Solar System Research, Göttingen, Germany
| | - T Platz
- Max-Planck Institute for Solar System Research, Göttingen, Germany
| | | | - R Jaumann
- German Aerospace Center (DLR), Berlin, Germany. Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - J C Castillo-Rogez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - O Ruesch
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - B Schmidt
- Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - R S Park
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - F Preusker
- German Aerospace Center (DLR), Berlin, Germany
| | - D L Buczkowski
- John Hopkins Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C T Russell
- Department of Earth and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
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43
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Ruesch O, Platz T, Schenk P, McFadden LA, Castillo-Rogez JC, Quick LC, Byrne S, Preusker F, O’Brien DP, Schmedemann N, Williams DA, Li JY, Bland MT, Hiesinger H, Kneissl T, Neesemann A, Schaefer M, Pasckert JH, Schmidt BE, Buczkowski DL, Sykes MV, Nathues A, Roatsch T, Hoffmann M, Raymond CA, Russell CT. Cryovolcanism on Ceres. Science 2016; 353:353/6303/aaf4286. [DOI: 10.1126/science.aaf4286] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/20/2016] [Indexed: 11/02/2022]
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44
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Buczkowski DL, Schmidt BE, Williams DA, Mest SC, Scully JEC, Ermakov AI, Preusker F, Schenk P, Otto KA, Hiesinger H, O'Brien D, Marchi S, Sizemore H, Hughson K, Chilton H, Bland M, Byrne S, Schorghofer N, Platz T, Jaumann R, Roatsch T, Sykes MV, Nathues A, De Sanctis MC, Raymond CA, Russell CT. The geomorphology of Ceres. Science 2016; 353:353/6303/aaf4332. [PMID: 27701088 DOI: 10.1126/science.aaf4332] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 07/22/2016] [Indexed: 11/02/2022]
Abstract
Analysis of Dawn spacecraft Framing Camera image data allows evaluation of the topography and geomorphology of features on the surface of Ceres. The dwarf planet is dominated by numerous craters, but other features are also common. Linear structures include both those associated with impact craters and those that do not appear to have any correlation to an impact event. Abundant lobate flows are identified, and numerous domical features are found at a range of scales. Features suggestive of near-surface ice, cryomagmatism, and cryovolcanism have been identified. Although spectroscopic analysis has currently detected surface water ice at only one location on Ceres, the identification of these potentially ice-related features suggests that there may be at least some ice in localized regions in the crust.
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Affiliation(s)
- D L Buczkowski
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.
| | - B E Schmidt
- Georgia Institute of Technology, Atlanta, GA 30332, USA
| | | | - S C Mest
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - J E C Scully
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - A I Ermakov
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - F Preusker
- German Aerospace Center (DLR), Berlin 12489, Germany
| | - P Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - K A Otto
- German Aerospace Center (DLR), Berlin 12489, Germany
| | - H Hiesinger
- Westfälische Wilhelms-Universität Münster, Münster 48149, Germany
| | - D O'Brien
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H Sizemore
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - K Hughson
- University of California, Los Angeles, CA 90095, USA
| | - H Chilton
- Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - M Bland
- United States Geological Survey, Flagstaff, AZ 86001, USA
| | - S Byrne
- Lunar and Planetary Laboratory, Tucson, AZ 85721, USA
| | - N Schorghofer
- University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - T Platz
- Max Planck Institute for Solar System Research, Göttingen 37077, Germany
| | - R Jaumann
- German Aerospace Center (DLR), Berlin 12489, Germany
| | - T Roatsch
- German Aerospace Center (DLR), Berlin 12489, Germany
| | - M V Sykes
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - A Nathues
- Max Planck Institute for Solar System Research, Göttingen 37077, Germany
| | - M C De Sanctis
- Istituto di Astrofisica e Planetologia Spaziale INAF, Rome 00133, Italy
| | - C A Raymond
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - C T Russell
- University of California, Los Angeles, CA 90095, USA
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45
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Ammannito E, DeSanctis MC, Ciarniello M, Frigeri A, Carrozzo FG, Combe JP, Ehlmann BL, Marchi S, McSween HY, Raponi A, Toplis MJ, Tosi F, Castillo-Rogez JC, Capaccioni F, Capria MT, Fonte S, Giardino M, Jaumann R, Longobardo A, Joy SP, Magni G, McCord TB, McFadden LA, Palomba E, Pieters CM, Polanskey CA, Rayman MD, Raymond CA, Schenk PM, Zambon F, Russell CT. Distribution of phyllosilicates on the surface of Ceres. Science 2016; 353:353/6303/aaf4279. [PMID: 27701086 DOI: 10.1126/science.aaf4279] [Citation(s) in RCA: 146] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/29/2016] [Indexed: 11/02/2022]
Abstract
The dwarf planet Ceres is known to host phyllosilicate minerals at its surface, but their distribution and origin have not previously been determined. We used the spectrometer onboard the Dawn spacecraft to map their spatial distribution on the basis of diagnostic absorption features in the visible and near-infrared spectral range (0.25 to 5.0 micrometers). We found that magnesium- and ammonium-bearing minerals are ubiquitous across the surface. Variations in the strength of the absorption features are spatially correlated and indicate considerable variability in the relative abundance of the phyllosilicates, although their composition is fairly uniform. These data, along with the distinctive spectral properties of Ceres relative to other asteroids and carbonaceous meteorites, indicate that the phyllosilicates were formed endogenously by a globally widespread and extensive alteration process.
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Affiliation(s)
- E Ammannito
- Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA.
| | - M C DeSanctis
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M Ciarniello
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - A Frigeri
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - F G Carrozzo
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - J-Ph Combe
- The Bear Fight Institute, Winthrop, WA 98862, USA
| | - B L Ehlmann
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - S Marchi
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H Y McSween
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996-1410, USA
| | - A Raponi
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M J Toplis
- Institut de Recherche en Astrophysique et Planétologie (UMR 5277), Université de Toulouse, F-31400 Toulouse, France
| | - F Tosi
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - J C Castillo-Rogez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - F Capaccioni
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M T Capria
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - S Fonte
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - M Giardino
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - R Jaumann
- Institute of Planetary Research, Deutsches Zentrum für Luft- und Raumfahrt, 12489 Berlin, Germany
| | - A Longobardo
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - S P Joy
- Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
| | - G Magni
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - T B McCord
- The Bear Fight Institute, Winthrop, WA 98862, USA
| | - L A McFadden
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - E Palomba
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - C M Pieters
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - C A Polanskey
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M D Rayman
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - P M Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - F Zambon
- Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy
| | - C T Russell
- Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA
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Park RS, Konopliv AS, Bills BG, Rambaux N, Castillo-Rogez JC, Raymond CA, Vaughan AT, Ermakov AI, Zuber MT, Fu RR, Toplis MJ, Russell CT, Nathues A, Preusker F. A partially differentiated interior for (1) Ceres deduced from its gravity field and shape. Nature 2016; 537:515-517. [PMID: 27487219 DOI: 10.1038/nature18955] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 05/27/2016] [Indexed: 11/09/2022]
Abstract
Remote observations of the asteroid (1) Ceres from ground- and space-based telescopes have provided its approximate density and shape, leading to a range of models for the interior of Ceres, from homogeneous to fully differentiated. A previously missing parameter that can place a strong constraint on the interior of Ceres is its moment of inertia, which requires the measurement of its gravitational variation together with either precession rate or a validated assumption of hydrostatic equilibrium. However, Earth-based remote observations cannot measure gravity variations and the magnitude of the precession rate is too small to be detected. Here we report gravity and shape measurements of Ceres obtained from the Dawn spacecraft, showing that it is in hydrostatic equilibrium with its inferred normalized mean moment of inertia of 0.37. These data show that Ceres is a partially differentiated body, with a rocky core overlaid by a volatile-rich shell, as predicted in some studies. Furthermore, we show that the gravity signal is strongly suppressed compared to that predicted by the topographic variation. This indicates that Ceres is isostatically compensated, such that topographic highs are supported by displacement of a denser interior. In contrast to the asteroid (4) Vesta, this strong compensation points to the presence of a lower-viscosity layer at depth, probably reflecting a thermal rather than compositional gradient. To further investigate the interior structure, we assume a two-layer model for the interior of Ceres with a core density of 2,460-2,900 kilograms per cubic metre (that is, composed of CI and CM chondrites), which yields an outer-shell thickness of 70-190 kilometres. The density of this outer shell is 1,680-1,950 kilograms per cubic metre, indicating a mixture of volatiles and denser materials such as silicates and salts. Although the gravity and shape data confirm that the interior of Ceres evolved thermally, its partially differentiated interior indicates an evolution more complex than has been envisioned for mid-sized (less than 1,000 kilometres across) ice-rich rocky bodies.
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Affiliation(s)
- R S Park
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - A S Konopliv
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - B G Bills
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - N Rambaux
- IMCCE, Observatoire de Paris-PSL Research University, Sorbonne Universités-UPMC Université Paris 06, Université Lille 1, CNRS, 77 avenue Denfert-Rochereau, 75014 Paris, France
| | - J C Castillo-Rogez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - C A Raymond
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - A T Vaughan
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - A I Ermakov
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - M T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - R R Fu
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA
| | - M J Toplis
- Institut de Recherche en Astrophysique et Planetologie, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - C T Russell
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90095-1567, USA
| | - A Nathues
- Max Planck Institute for Solar System Research, Goettingen, Germany
| | - F Preusker
- Institute of Planetary Research, DLR, Department of Planetary Geodesy, Rutherfordstrasse 2, 12489 Berlin, Germany
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47
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Eriksson S, Wilder FD, Ergun RE, Schwartz SJ, Cassak PA, Burch JL, Chen LJ, Torbert RB, Phan TD, Lavraud B, Goodrich KA, Holmes JC, Stawarz JE, Sturner AP, Malaspina DM, Usanova ME, Trattner KJ, Strangeway RJ, Russell CT, Pollock CJ, Giles BL, Hesse M, Lindqvist PA, Drake JF, Shay MA, Nakamura R, Marklund GT. Magnetospheric Multiscale Observations of the Electron Diffusion Region of Large Guide Field Magnetic Reconnection. Phys Rev Lett 2016; 117:015001. [PMID: 27419573 DOI: 10.1103/physrevlett.117.015001] [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: 04/13/2016] [Indexed: 06/06/2023]
Abstract
We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E_{∥}) that is larger than predicted by simulations. The high-speed (∼300 km/s) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E_{∥} is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure.
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Affiliation(s)
- S Eriksson
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - F D Wilder
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - R E Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S J Schwartz
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- The Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - P A Cassak
- West Virginia University, Morgantown, West Virginia 26506, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
| | - L-J Chen
- University of Maryland, College Park, Maryland 20742, USA
| | - R B Torbert
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, 31028 Toulouse, France
- Centre National de la Recherche Scientifique, UMR 5277, Toulouse, France
| | - K A Goodrich
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J C Holmes
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J E Stawarz
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - A P Sturner
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D M Malaspina
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - M E Usanova
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - K J Trattner
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, SE-11428 Stockholm, Sweden
| | - J F Drake
- University of Maryland, College Park, Maryland 20742, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, 8042 Graz, Austria
| | - G T Marklund
- KTH Royal Institute of Technology, SE-11428 Stockholm, Sweden
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48
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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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49
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Ergun RE, Goodrich KA, Wilder FD, Holmes JC, Stawarz JE, Eriksson S, Sturner AP, Malaspina DM, Usanova ME, Torbert RB, Lindqvist PA, Khotyaintsev Y, Burch JL, Strangeway RJ, Russell CT, Pollock CJ, Giles BL, Hesse M, Chen LJ, Lapenta G, Goldman MV, Newman DL, Schwartz SJ, Eastwood JP, Phan TD, Mozer FS, Drake J, Shay MA, Cassak PA, Nakamura R, Marklund G. Magnetospheric Multiscale Satellites Observations of Parallel Electric Fields Associated with Magnetic Reconnection. Phys Rev Lett 2016; 116:235102. [PMID: 27341241 DOI: 10.1103/physrevlett.116.235102] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Indexed: 06/06/2023]
Abstract
We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E_{∥}) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E_{∥} events near the electron diffusion region have amplitudes on the order of 100 mV/m, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E_{∥} events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E_{∥} events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.
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Affiliation(s)
- R E Ergun
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - K A Goodrich
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - F D Wilder
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J C Holmes
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J E Stawarz
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S Eriksson
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - A P Sturner
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D M Malaspina
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - M E Usanova
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm, Sweden
| | - Y Khotyaintsev
- Swedish Institute of Space Physics (Uppsala), Uppsala, Sweden
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L J Chen
- University of Maryland, College Park, Maryland 20742, USA
| | - G Lapenta
- Leuven Universiteit, Leuven, Belgium
| | - M V Goldman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - D L Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - S J Schwartz
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- The Blackett Laboratory, Imperial College London, United Kingdom
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, United Kingdom
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - F S Mozer
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J Drake
- University of Maryland, College Park, Maryland 20742, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - P A Cassak
- West Virginia University, Morgantown, West Virginia 26506, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - G Marklund
- KTH Royal Institute of Technology, Stockholm, Sweden
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50
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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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