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Goetz C, Scharré L, Wedlund CS, Moeslinger A, Nilsson H, Odelstad E, Taylor MGGT, Volwerk M. Solar Wind Protons in the Diamagnetic Cavity at Comet 67P/Churyumov-Gerasimenko. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2022JA031249. [PMID: 38440350 PMCID: PMC10909421 DOI: 10.1029/2022ja031249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 03/09/2023] [Accepted: 03/28/2023] [Indexed: 03/06/2024]
Abstract
The plasma environment at a comet can be divided into different regions with distinct plasma characteristics. Two such regions are the solar wind ion cavity, which refers to the part of the outer coma that does not contain any solar wind ions anymore; and the diamagnetic cavity, which is the region of unmagnetized plasma in the innermost coma. From theory and previous observations, it was thought that under usual circumstances no solar wind ion should be observable near or inside of the diamagnetic cavity. For the first time, we report on five observations that show that protons near solar wind energies can also be found inside the diamagnetic cavity. We characterize these proton signatures, where and when they occur, and discuss possible mechanisms that could lead to protons penetrating the inner coma and traversing the diamagnetic cavity boundary. By understanding these observations, we hope to better understand the interaction region of the comet with the solar wind under nonstandard conditions. The protons detected inside the diamagnetic cavity have directions and energies consistent with protons of solar wind origin. The five events occur only at intermediate gas production rates and low cometocentric distances. Charge transfer reactions, high solar wind dynamic pressure and a neutral gas outburst can be ruled out as causes. We suggest that the anomalous appearance of protons in the diamagnetic cavity is due to a specific solar wind configuration where the solar wind velocity is parallel to the interplanetary magnetic field, thus inhibiting mass-loading and deflection.
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Affiliation(s)
- Charlotte Goetz
- Department of Mathematics, Physics and Electrical EngineeringNorthumbria UniversityNewcastle‐upon‐TyneUK
- European Space Research and Technology CentreEuropean Space AgencyNoordwijkThe Netherlands
| | - Lucie Scharré
- Old CollegeUniversity of EdinburghEdinburghUK
- Institute for Physics, Laboratory for Galaxy Evolution and Spectral ModellingEcole Polytechnique Federale de Lausanne, Observatoire de SauvernyVersoixSwitzerland
| | | | | | | | | | | | - Martin Volwerk
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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2
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Goetz C, Behar E, Beth A, Bodewits D, Bromley S, Burch J, Deca J, Divin A, Eriksson AI, Feldman PD, Galand M, Gunell H, Henri P, Heritier K, Jones GH, Mandt KE, Nilsson H, Noonan JW, Odelstad E, Parker JW, Rubin M, Simon Wedlund C, Stephenson P, Taylor MGGT, Vigren E, Vines SK, Volwerk M. The Plasma Environment of Comet 67P/Churyumov-Gerasimenko. SPACE SCIENCE REVIEWS 2022; 218:65. [PMID: 36397966 PMCID: PMC9649581 DOI: 10.1007/s11214-022-00931-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 10/20/2022] [Indexed: 06/04/2023]
Abstract
The environment of a comet is a fascinating and unique laboratory to study plasma processes and the formation of structures such as shocks and discontinuities from electron scales to ion scales and above. The European Space Agency's Rosetta mission collected data for more than two years, from the rendezvous with comet 67P/Churyumov-Gerasimenko in August 2014 until the final touch-down of the spacecraft end of September 2016. This escort phase spanned a large arc of the comet's orbit around the Sun, including its perihelion and corresponding to heliocentric distances between 3.8 AU and 1.24 AU. The length of the active mission together with this span in heliocentric and cometocentric distances make the Rosetta data set unique and much richer than sets obtained with previous cometary probes. Here, we review the results from the Rosetta mission that pertain to the plasma environment. We detail all known sources and losses of the plasma and typical processes within it. The findings from in-situ plasma measurements are complemented by remote observations of emissions from the plasma. Overviews of the methods and instruments used in the study are given as well as a short review of the Rosetta mission. The long duration of the Rosetta mission provides the opportunity to better understand how the importance of these processes changes depending on parameters like the outgassing rate and the solar wind conditions. We discuss how the shape and existence of large scale structures depend on these parameters and how the plasma within different regions of the plasma environment can be characterised. We end with a non-exhaustive list of still open questions, as well as suggestions on how to answer them in the future.
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Affiliation(s)
- Charlotte Goetz
- ESTEC, European Space Agency, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle-upon-Tyne, UK
| | - Etienne Behar
- Swedish Institute of Space Physics, Box 812, 981 28 Kiruna, Sweden
- Lagrange, OCA, UCA, CNRS, Nice, France
| | - Arnaud Beth
- Department of Physics, Umeå University, 901 87 Umeå, Sweden
| | - Dennis Bodewits
- Physics Department, Leach Science Center, Auburn University, Auburn, AL 36832 USA
| | - Steve Bromley
- Physics Department, Leach Science Center, Auburn University, Auburn, AL 36832 USA
| | - Jim Burch
- Southwest Research Institute, P.O. Drawer 28510, San Antonio, TX 78228-0510 USA
| | - Jan Deca
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, 3665 Discovery Drive, Boulder, CO 80303 USA
| | - Andrey Divin
- Earth Physics Department, St. Petersburg State University, Ulianovskaya, 1, St Petersburg, 198504 Russia
| | | | - Paul D. Feldman
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 USA
| | - Marina Galand
- Department of Physics, Imperial College London, Prince Consort Road, London, SW7 2AZ UK
| | - Herbert Gunell
- Department of Physics, Umeå University, 901 87 Umeå, Sweden
| | - Pierre Henri
- Lagrange, OCA, UCA, CNRS, Nice, France
- LPC2E, CNRS, Orléans, France
| | - Kevin Heritier
- Department of Physics, Imperial College London, Prince Consort Road, London, SW7 2AZ UK
| | - Geraint H. Jones
- UCL Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, RH5 6NT UK
- The Centre for Planetary Sciences at UCL/Birkbeck, Gower Street, London, WC1E 6BT UK
| | | | - Hans Nilsson
- Swedish Institute of Space Physics, Box 812, 981 28 Kiruna, Sweden
| | - John W. Noonan
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85719 USA
| | - Elias Odelstad
- Swedish Institute of Space Physics, Box 537, SE-751 21 Uppsala, Sweden
| | | | - Martin Rubin
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
| | - Cyril Simon Wedlund
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8042 Graz, Austria
| | - Peter Stephenson
- Department of Physics, Imperial College London, Prince Consort Road, London, SW7 2AZ UK
| | | | - Erik Vigren
- Swedish Institute of Space Physics, Box 537, SE-751 21 Uppsala, Sweden
| | - Sarah K. Vines
- Johns Hopkins Applied Physics Laboratory, Laurel, MD 20723 USA
| | - Martin Volwerk
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8042 Graz, Austria
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3
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Wu SY, Ye SY, Fischer G, Taubenschuss U, Jackman CM, O'Dwyer E, Kurth WS, Yao S, Yao ZH, Menietti JD, Xu Y, Long MY, Cecconi B. Saturn Anomalous Myriametric Radiation, a New Type of Saturn Radio Emission Revealed by Cassini. GEOPHYSICAL RESEARCH LETTERS 2022; 49:e2022GL099237. [PMID: 36249464 PMCID: PMC9541930 DOI: 10.1029/2022gl099237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 06/16/2023]
Abstract
A new radio component namely Saturn Anomalous Myriametric Radiation (SAM) is reported. A total of 193 SAM events have been identified by using all the Cassini Saturn orbital data. SAM emissions are L-O mode radio emission and occasionally accompanied by a first harmonic in R-X mode. SAM's intensities decrease with increasing distance from Saturn, suggesting a source near Saturn. SAM has a typical central frequency near 13 kHz, a bandwidth greater than 8 kHz and usually drifts in frequency over time. SAM's duration can extend to near 11 hr and even longer. These features distinguish SAM from the regular narrowband emissions observed in the nearby frequency range, hence the name anomalous. The high occurrence rate of SAM after low frequency extensions of Saturn Kilometric Radiation and the SAM cases observed during compressions of Saturn's magnetosphere suggest a special connection to solar wind dynamics and magnetospheric conditions at Saturn.
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Affiliation(s)
- S. Y. Wu
- Department of Earth and Space SciencesSouthern University of Science and TechnologyShenzhenPeople's Republic of China
- LESIAObservatoire de ParisUniversité PSLCNRSSorbonne UniversitéUniversité de ParisMeudonFrance
| | - S. Y. Ye
- Department of Earth and Space SciencesSouthern University of Science and TechnologyShenzhenPeople's Republic of China
| | - G. Fischer
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - U. Taubenschuss
- Department of Space PhysicsInstitute of Atmospheric Physics of the Czech Academy of SciencesPragueCzechia
| | - C. M. Jackman
- School of Cosmic PhysicsDIAS Dunsink ObservatoryDublin Institute for Advanced StudiesDublinIreland
| | - E. O'Dwyer
- School of Cosmic PhysicsDIAS Dunsink ObservatoryDublin Institute for Advanced StudiesDublinIreland
| | - W. S. Kurth
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - S. Yao
- School of Geophysics and Information TechnologyChina University of Geosciences (Beijing)BeijingPeople's Republic of China
| | - Z. H. Yao
- Key Laboratory of Earth and Planetary PhysicsInstitute of Geology and GeophysicsChinese Academy of SciencesBeijingPeople's Republic of China
| | - J. D. Menietti
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - Y. Xu
- Key Laboratory of Earth and Planetary PhysicsInstitute of Geology and GeophysicsChinese Academy of SciencesBeijingPeople's Republic of China
| | - M. Y. Long
- Department of Space PhysicsSchool of Electronic InformationWuhan UniversityWuhanPeople's Republic of China
| | - B. Cecconi
- LESIAObservatoire de ParisUniversité PSLCNRSSorbonne UniversitéUniversité de ParisMeudonFrance
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4
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Andrews DJ, Barabash S, Edberg NJT, Gurnett DA, Hall BES, Holmström M, Lester M, Morgan DD, Opgenoorth HJ, Ramstad R, Sanchez-Cano B, Way M, Witasse O. Plasma observations during the Mars atmospheric "plume" event of March-April 2012. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:3139-3154. [PMID: 29552437 PMCID: PMC5854877 DOI: 10.1002/2015ja022023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We present initial analysis and conclusions from plasma observations made during the reported "Mars plume event" of March - April 2012. During this period, multiple independent amateur observers detected a localized, high-altitude "plume" over the Martian dawn terminator [Sanchez-Lavega et al., Nature, 2015, doi:10.1038/nature14162], the cause of which remains to be explained. The estimated brightness of the plume exceeds that expected for auroral emissions, and its projected altitude greatly exceeds that at which clouds are expected to form. We report on in-situ measurements of ionospheric plasma density and solar wind parameters throughout this interval made by Mars Express, obtained over the same surface region, but at the opposing terminator. Measurements in the ionosphere at the corresponding location frequently show a disturbed structure, though this is not atypical for such regions with intense crustal magnetic fields. We tentatively conclude that the formation and/or transport of this plume to the altitudes where it was observed could be due in part to the result of a large interplanetary coronal mass ejection (ICME) encountering the Martian system. Interestingly, we note that the only similar plume detection in May 1997 may also have been associated with a large ICME impact at Mars.
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Affiliation(s)
- D J Andrews
- Swedish Institute of Space Physics (Uppsala), Uppsala, Sweden
| | - S Barabash
- Swedish Institute of Space Physics (Kiruna), Kiruna, Sweden
| | - N J T Edberg
- Swedish Institute of Space Physics (Uppsala), Uppsala, Sweden
| | - D A Gurnett
- Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa, USA
| | - B E S Hall
- Department of Physics and Astronomy, University of Leicester, Leicester, United Kingdom
| | - M Holmström
- Swedish Institute of Space Physics (Kiruna), Kiruna, Sweden
| | - M Lester
- Department of Physics and Astronomy, University of Leicester, Leicester, United Kingdom
| | - D D Morgan
- Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa, USA
| | - H J Opgenoorth
- Swedish Institute of Space Physics (Uppsala), Uppsala, Sweden
| | - R Ramstad
- Swedish Institute of Space Physics (Kiruna), Kiruna, Sweden
| | - B Sanchez-Cano
- Department of Physics and Astronomy, University of Leicester, Leicester, United Kingdom
| | - M Way
- NASA Goddard Institute for Space Studies, 2880 Broadway, New York, New York, USA
- Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20, Uppsala, Sweden
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5
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Dunn WR, Branduardi-Raymont G, Elsner RF, Vogt MF, Lamy L, Ford PG, Coates AJ, Gladstone GR, Jackman CM, Nichols JD, Rae IJ, Varsani A, Kimura T, Hansen KC, Jasinski JM. The impact of an ICME on the Jovian X-ray aurora. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:2274-2307. [PMID: 27867794 PMCID: PMC5111422 DOI: 10.1002/2015ja021888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 01/11/2016] [Accepted: 01/27/2016] [Indexed: 06/06/2023]
Abstract
We report the first Jupiter X-ray observations planned to coincide with an interplanetary coronal mass ejection (ICME). At the predicted ICME arrival time, we observed a factor of ∼8 enhancement in Jupiter's X-ray aurora. Within 1.5 h of this enhancement, intense bursts of non-Io decametric radio emission occurred. Spatial, spectral, and temporal characteristics also varied between ICME arrival and another X-ray observation two days later. Gladstone et al. (2002) discovered the polar X-ray hot spot and found it pulsed with 45 min quasiperiodicity. During the ICME arrival, the hot spot expanded and exhibited two periods: 26 min periodicity from sulfur ions and 12 min periodicity from a mixture of carbon/sulfur and oxygen ions. After the ICME, the dominant period became 42 min. By comparing Vogt et al. (2011) Jovian mapping models with spectral analysis, we found that during ICME arrival at least two distinct ion populations, from Jupiter's dayside, produced the X-ray aurora. Auroras mapping to magnetospheric field lines between 50 and 70 RJ were dominated by emission from precipitating sulfur ions (S7+,…,14+). Emissions mapping to closed field lines between 70 and 120 RJ and to open field lines were generated by a mixture of precipitating oxygen (O7+,8+) and sulfur/carbon ions, possibly implying some solar wind precipitation. We suggest that the best explanation for the X-ray hot spot is pulsed dayside reconnection perturbing magnetospheric downward currents, as proposed by Bunce et al. (2004). The auroral enhancement has different spectral, spatial, and temporal characteristics to the hot spot. By analyzing these characteristics and coincident radio emissions, we propose that the enhancement is driven directly by the ICME through Jovian magnetosphere compression and/or a large-scale dayside reconnection event.
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Affiliation(s)
- William R Dunn
- Mullard Space Science Laboratory, Department of Space and Climate Physics University College London Dorking UK; Centre for Planetary Science UCL/Birkbeck London UK
| | | | - Ronald F Elsner
- ZP12, NASA Marshall Space Flight Center Huntsville Alabama USA
| | - Marissa F Vogt
- Center for Space Physics Boston University Boston Massachusetts USA
| | - Laurent Lamy
- LESIA, Observatoire de Paris, CNRS, UPMC Université Paris Diderot Meudon France
| | - Peter G Ford
- Kavli Institute for Astrophysics and Space Research MIT Cambridge Massachusetts USA
| | - Andrew J Coates
- Mullard Space Science Laboratory, Department of Space and Climate Physics University College London Dorking UK; Centre for Planetary Science UCL/Birkbeck London UK
| | - G Randall Gladstone
- Space Science and Engineering Division Southwest Research Institute San Antonio Texas USA
| | - Caitriona M Jackman
- Department of Physics and Astronomy University of Southampton Southampton UK
| | - Jonathan D Nichols
- Department of Physics and Astronomy University of Leicester Leicester UK
| | - I Jonathan Rae
- Mullard Space Science Laboratory, Department of Space and Climate Physics University College London Dorking UK
| | - Ali Varsani
- Mullard Space Science Laboratory, Department of Space and Climate Physics University College London Dorking UK; Space Research Institute Austrian Academy of Sciences Graz Austria
| | - Tomoki Kimura
- Institute of Space and Astronautical Science Japan Aerospace Exploration Agency Sagamihara Japan; Nishina Center for Accelerator-Based Science RIKEN Wako Japan
| | - Kenneth C Hansen
- Department of Atmospheric, Oceanic and Space Sciences University of Michigan Ann Arbor Michigan USA
| | - Jamie M Jasinski
- Mullard Space Science Laboratory, Department of Space and Climate Physics University College London Dorking UK; Centre for Planetary Science UCL/Birkbeck London UK; Department of Atmospheric, Oceanic and Space Sciences University of Michigan Ann Arbor Michigan USA
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6
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Felici M, Arridge CS, Coates AJ, Badman SV, Dougherty MK, Jackman CM, Kurth WS, Melin H, Mitchell DG, Reisenfeld DB, Sergis N. Cassini observations of ionospheric plasma in Saturn's magnetotail lobes. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:338-357. [PMID: 27610291 PMCID: PMC4994772 DOI: 10.1002/2015ja021648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 12/13/2015] [Accepted: 12/28/2015] [Indexed: 05/20/2023]
Abstract
Studies of Saturn's magnetosphere with the Cassini mission have established the importance of Enceladus as the dominant mass source for Saturn's magnetosphere. It is well known that the ionosphere is an important mass source at Earth during periods of intense geomagnetic activity, but lesser attention has been dedicated to study the ionospheric mass source at Saturn. In this paper we describe a case study of data from Saturn's magnetotail, when Cassini was located at ≃ 2200 h Saturn local time at 36 RS from Saturn. During several entries into the magnetotail lobe, tailward flowing cold electrons and a cold ion beam were observed directly adjacent to the plasma sheet and extending deeper into the lobe. The electrons and ions appear to be dispersed, dropping to lower energies with time. The composition of both the plasma sheet and lobe ions show very low fluxes (sometimes zero within measurement error) of water group ions. The magnetic field has a swept-forward configuration which is atypical for this region, and the total magnetic field strength is larger than expected at this distance from the planet. Ultraviolet auroral observations show a dawn brightening, and upstream heliospheric models suggest that the magnetosphere is being compressed by a region of high solar wind ram pressure. We interpret this event as the observation of ionospheric outflow in Saturn's magnetotail. We estimate a number flux between (2.95 ± 0.43) × 109 and (1.43 ± 0.21) × 1010 cm-2 s-1, 1 or about 2 orders of magnitude larger than suggested by steady state MHD models, with a mass source between 1.4 ×102 and 1.1 ×103 kg/s. After considering several configurations for the active atmospheric regions, we consider as most probable the main auroral oval, with associated mass source between 49.7 ±13.4 and 239.8 ±64.8 kg/s for an average auroral oval, and 10 ±4 and 49 ±23 kg/s for the specific auroral oval morphology found during this event. It is not clear how much of this mass is trapped within the magnetosphere and how much is lost to the solar wind.
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Affiliation(s)
- M. Felici
- Mullard Space Science LaboratoryUniversity College LondonDorkingUK
- Centre for Planetary Sciences at UCL/BirkbeckLondonUK
- Department of PhysicsLancaster UniversityLancasterUK
| | - C. S. Arridge
- Department of PhysicsLancaster UniversityLancasterUK
| | - A. J. Coates
- Mullard Space Science LaboratoryUniversity College LondonDorkingUK
- Centre for Planetary Sciences at UCL/BirkbeckLondonUK
| | - S. V. Badman
- Department of PhysicsLancaster UniversityLancasterUK
| | - M. K. Dougherty
- Space and Atmospheric Physics Group, The Blackett LaboratoryImperial College LondonLondonUK
| | - C. M. Jackman
- Department of Physics and AstronomyUniversity of SouthamptonSouthamptonUK
| | - W. S. Kurth
- Department of Physics and AstronomyUniversity of IowaIowa CityIowaUSA
| | - H. Melin
- Department of Physics and AstronomyUniversity of LeicesterLeicesterUK
| | - D. G. Mitchell
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - D. B. Reisenfeld
- Department of Physics and AstronomyUniversity of MontanaMissoulaMontanaUSA
| | - N. Sergis
- Mullard Space Science LaboratoryUniversity College LondonDorkingUK
- Office for Space ResearchAcademy of AthensAthensGreece
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7
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Jackman CM, Thomsen MF, Mitchell DG, Sergis N, Arridge CS, Felici M, Badman SV, Paranicas C, Jia X, Hospodarksy GB, Andriopoulou M, Khurana KK, Smith AW, Dougherty MK. Field dipolarization in Saturn's magnetotail with planetward ion flows and energetic particle flow bursts: Evidence of quasi-steady reconnection. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2015; 120:3603-3617. [PMID: 27570722 PMCID: PMC4981121 DOI: 10.1002/2015ja020995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 04/01/2015] [Accepted: 04/01/2015] [Indexed: 05/20/2023]
Abstract
We present a case study of an event from 20 August (day 232) of 2006, when the Cassini spacecraft was sampling the region near 32 RS and 22 h LT in Saturn's magnetotail. Cassini observed a strong northward-to-southward turning of the magnetic field, which is interpreted as the signature of dipolarization of the field as seen by the spacecraft planetward of the reconnection X line. This event was accompanied by very rapid (up to ~1500 km s-1) thermal plasma flow toward the planet. At energies above 28 keV, energetic hydrogen and oxygen ion flow bursts were observed to stream planetward from a reconnection site downtail of the spacecraft. Meanwhile, a strong field-aligned beam of energetic hydrogen was also observed to stream tailward, likely from an ionospheric source. Saturn kilometric radiation emissions were stimulated shortly after the observation of the dipolarization. We discuss the field, plasma, energetic particle, and radio observations in the context of the impact this reconnection event had on global magnetospheric dynamics.
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Affiliation(s)
- C. M. Jackman
- School of Physics and AstronomyUniversity of SouthamptonSouthamptonUK
| | | | - D. G. Mitchell
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | | | | | - M. Felici
- Department of PhysicsLancaster UniversityBailriggUK
- Mullard Space Science LaboratoryUniversity College LondonSurreyUK
- The Centre for Planetary Sciences at UCL/BirkbeckLondonUK
| | - S. V. Badman
- Department of PhysicsLancaster UniversityBailriggUK
| | - C. Paranicas
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - X. Jia
- Atmospheric, Oceanic and Space SciencesUniversity of MichiganAnn ArborMichiganUSA
| | - G. B. Hospodarksy
- Department of Physics and AstronomyUniversity of IowaIowa CityIowaUSA
| | - M. Andriopoulou
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - K. K. Khurana
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - A. W. Smith
- School of Physics and AstronomyUniversity of SouthamptonSouthamptonUK
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8
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Jia X, Hansen KC, Gombosi TI, Kivelson MG, Tóth G, DeZeeuw DL, Ridley AJ. Magnetospheric configuration and dynamics of Saturn's magnetosphere: A global MHD simulation. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012ja017575] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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9
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Went DR, Hospodarsky GB, Masters A, Hansen KC, Dougherty MK. A new semiempirical model of Saturn's bow shock based on propagated solar wind parameters. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010ja016349] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- D. R. Went
- Blackett Laboratory; Imperial College London; London UK
| | - G. B. Hospodarsky
- Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
| | - A. Masters
- Centre for Planetary Sciences; University College London/Birkbeck; London UK
- Mullard Space Science Laboratory, Department of Space and Climate Physics; University College London; Dorking UK
| | - K. C. Hansen
- Space Research Building; University of Michigan; Ann Arbor Michigan USA
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10
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Jackman CM, Arridge CS, Slavin JA, Milan SE, Lamy L, Dougherty MK, Coates AJ. In situ observations of the effect of a solar wind compression on Saturn's magnetotail. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010ja015312] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- C. M. Jackman
- Blackett Laboratory; Imperial College London; London UK
| | - C. S. Arridge
- Mullard Space Science Laboratory, Department of Space and Climate Physics; University College London; Dorking UK
- The Centre for Planetary Sciences at UCL/Birkbeck; London UK
| | - J. A. Slavin
- Heliophysics Science Division; NASA Goddard Space Flight Center; Greenbelt Maryland USA
| | - S. E. Milan
- Radio and Space Plasma Physics Group; University of Leicester; Leicester UK
| | - L. Lamy
- Blackett Laboratory; Imperial College London; London UK
| | | | - A. J. Coates
- Mullard Space Science Laboratory, Department of Space and Climate Physics; University College London; Dorking UK
- The Centre for Planetary Sciences at UCL/Birkbeck; London UK
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11
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Zieger B, Hansen KC, Gombosi TI, De Zeeuw DL. Periodic plasma escape from the mass-loaded Kronian magnetosphere. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009ja014951] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- B. Zieger
- Department of Atmospheric, Oceanic and Space Sciences; University of Michigan; Ann Arbor Michigan USA
| | - K. C. Hansen
- Department of Atmospheric, Oceanic and Space Sciences; University of Michigan; Ann Arbor Michigan USA
| | - T. I. Gombosi
- Department of Atmospheric, Oceanic and Space Sciences; University of Michigan; Ann Arbor Michigan USA
| | - D. L. De Zeeuw
- Department of Atmospheric, Oceanic and Space Sciences; University of Michigan; Ann Arbor Michigan USA
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12
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Clarke JT, Nichols J, Gérard JC, Grodent D, Hansen KC, Kurth W, Gladstone GR, Duval J, Wannawichian S, Bunce E, Cowley SWH, Crary F, Dougherty M, Lamy L, Mitchell D, Pryor W, Retherford K, Stallard T, Zieger B, Zarka P, Cecconi B. Response of Jupiter's and Saturn's auroral activity to the solar wind. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008ja013694] [Citation(s) in RCA: 141] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- J. T. Clarke
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - J. Nichols
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | | | - D. Grodent
- LPAP; Université de Liège; Liege Belgium
| | - K. C. Hansen
- AOSS Department; University of Michigan; Ann Arbor Michigan USA
| | - W. Kurth
- Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
| | | | - J. Duval
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - S. Wannawichian
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - E. Bunce
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - S. W. H. Cowley
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - F. Crary
- Southwest Research Institute; San Antonio Texas USA
| | - M. Dougherty
- Blackett Laboratory; Imperial College; London UK
| | - L. Lamy
- LESIA, Observatoire de Paris; UPMC, CNRS, Université Paris Diderot; Meudon France
| | - D. Mitchell
- Johns Hopkins University Applied Physics Laboratory; Laurel Maryland USA
| | - W. Pryor
- Department of Science; Central Arizona College; Coolidge Arizona USA
| | | | - T. Stallard
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - B. Zieger
- AOSS Department; University of Michigan; Ann Arbor Michigan USA
| | - P. Zarka
- LESIA, Observatoire de Paris; UPMC, CNRS, Université Paris Diderot; Meudon France
| | - B. Cecconi
- LESIA, Observatoire de Paris; UPMC, CNRS, Université Paris Diderot; Meudon France
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13
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Kellett S, Bunce EJ, Coates AJ, Cowley SWH. Thickness of Saturn's ring current determined from north-south Cassini passes through the current layer. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008ja013942] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- S. Kellett
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - E. J. Bunce
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - A. J. Coates
- Mullard Space Science Laboratory; University College London; Dorking UK
- Centre for Planetary Sciences; University College London; London UK
| | - S. W. H. Cowley
- Department of Physics and Astronomy; University of Leicester; Leicester UK
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14
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Bunce EJ, Arridge CS, Clarke JT, Coates AJ, Cowley SWH, Dougherty MK, Gérard JC, Grodent D, Hansen KC, Nichols JD, Southwood DJ, Talboys DL. Origin of Saturn's aurora: Simultaneous observations by Cassini and the Hubble Space Telescope. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008ja013257] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- E. J. Bunce
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - C. S. Arridge
- Mullard Space Science Laboratory; University College London; Dorking UK
| | - J. T. Clarke
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - A. J. Coates
- Mullard Space Science Laboratory; University College London; Dorking UK
| | - S. W. H. Cowley
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | | | - J.-C. Gérard
- Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liège Belgium
| | - D. Grodent
- Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liège Belgium
| | - K. C. Hansen
- Department of Atmospheric, Oceanic, and Space Sciences; University of Michigan; Ann Arbor Michigan USA
| | - J. D. Nichols
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - D. J. Southwood
- Blackett Laboratory; Imperial College; London UK
- European Space Agency, HQ; Paris France
| | - D. L. Talboys
- Department of Physics and Astronomy; University of Leicester; Leicester UK
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