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Szalay JR, Smith HT, Zirnstein EJ, McComas DJ, Begley LJ, Bagenal F, Delamere PA, Wilson RJ, Valek PW, Poppe AR, Nénon Q, Allegrini F, Ebert RW, Bolton SJ. Water-Group Pickup Ions From Europa-Genic Neutrals Orbiting Jupiter. Geophys Res Lett 2022; 49:e2022GL098111. [PMID: 35864892 PMCID: PMC9286426 DOI: 10.1029/2022gl098111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/07/2022] [Accepted: 04/08/2022] [Indexed: 06/15/2023]
Abstract
Water-group gas continuously escapes from Jupiter's icy moons to form co-orbiting populations of particles or neutral toroidal clouds. These clouds provide insights into their source moons as they reveal loss processes and compositions of their parent bodies, alter local plasma composition, and act as sources and sinks for magnetospheric particles. We report the first observations of H2 + pickup ions in Jupiter's magnetosphere from 13 to 18 Jovian radii and find a density ratio of H2 +/H+ = 8 ± 4%, confirming the presence of a neutral H2 toroidal cloud. Pickup ion densities monotonically decrease radially beyond 13 R J consistent with an advecting Europa-genic toroidal cloud source. From these observations, we derive a total H2 neutral loss rate from Europa of 1.2 ± 0.7 kg s-1. This provides the most direct estimate of Europa's H2 neutral loss rate to date and underscores the importance of both ion composition and neutral toroidal clouds in understanding satellite-magnetosphere interactions.
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Affiliation(s)
- J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - H. T. Smith
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - E. J. Zirnstein
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - D. J. McComas
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - L. J. Begley
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - P. A. Delamere
- Geophysical InstituteUniversity of Alaska FairbanksFairbanksAKUSA
| | - R. J. Wilson
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - P. W. Valek
- Southwest Research InstituteSan AntonioTXUSA
| | - A. R. Poppe
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - Q. Nénon
- Institut de Recherche en Astrophysique et PlanétologieCNRS‐UPS‐CNESToulouseFrance
| | - F. Allegrini
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - R. W. Ebert
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
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Allen RC, Paranicas CP, Bagenal F, Vines SK, Hamilton DC, Allegrini F, Clark G, Delamere PA, Kim TK, Krimigis SM, Mitchell DG, Smith TH, Wilson RJ. Energetic Oxygen and Sulfur Charge States in the Outer Jovian Magnetosphere: Insights From the Cassini Jupiter Flyby. Geophys Res Lett 2019; 46:11709-11717. [PMID: 31894172 PMCID: PMC6919296 DOI: 10.1029/2019gl085185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 08/28/2019] [Revised: 10/11/2019] [Accepted: 10/14/2019] [Indexed: 06/10/2023]
Abstract
On 10 January 2001, Cassini briefly entered into the magnetosphere of Jupiter, en route to Saturn. During this excursion into the Jovian magnetosphere, the Cassini Magnetosphere Imaging Instrument/Charge-Energy-Mass Spectrometer detected oxygen and sulfur ions. While Charge-Energy-Mass Spectrometer can distinguish between oxygen and sulfur charge states directly, only 95.9 ± 2.9 keV/e ions were sampled during this interval, allowing for a long time integration of the tenuous outer magnetospheric (~200 RJ) plasma at one energy. For this brief interval for the 95.9 keV/e ions, 96% of oxygen ions were O+, with the other 4% as O2+, while 25% of the energetic sulfur ions were S+, 42% S2+, and 33% S3+. The S2+/O+ flux ratio was observed to be 0.35 (±0.06 Poisson error).
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Affiliation(s)
- R. C. Allen
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - C. P. Paranicas
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - S. K. Vines
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - D. C. Hamilton
- Department of PhysicsUniversity of MarylandCollege ParkMDUSA
| | - F. Allegrini
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - G. Clark
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - P. A. Delamere
- Geophysical InstituteUniversity of Alaska FairbanksFairbanksAKUSA
| | - T. K. Kim
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - S. M. Krimigis
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - D. G. Mitchell
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - T. H. Smith
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - R. J. Wilson
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
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Bagenal F, Horányi M, McComas DJ, McNutt RL, Elliott HA, Hill ME, Brown LE, Delamere PA, Kollmann P, Krimigis SM, Kusterer M, Lisse CM, Mitchell DG, Piquette M, Poppe AR, Strobel DF, Szalay JR, Valek P, Vandegriff J, Weidner S, Zirnstein EJ, Stern SA, Ennico K, Olkin CB, Weaver HA, Young LA. Pluto's interaction with its space environment: Solar wind, energetic particles, and dust. Science 2016; 351:aad9045. [PMID: 26989259 DOI: 10.1126/science.aad9045] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The New Horizons spacecraft carried three instruments that measured the space environment near Pluto as it flew by on 14 July 2015. The Solar Wind Around Pluto (SWAP) instrument revealed an interaction region confined sunward of Pluto to within about 6 Pluto radii. The region's surprisingly small size is consistent with a reduced atmospheric escape rate, as well as a particularly high solar wind flux. Observations from the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) instrument suggest that ions are accelerated and/or deflected around Pluto. In the wake of the interaction region, PEPSSI observed suprathermal particle fluxes equal to about 1/10 of the flux in the interplanetary medium and increasing with distance downstream. The Venetia Burney Student Dust Counter, which measures grains with radii larger than 1.4 micrometers, detected one candidate impact in ±5 days around New Horizons' closest approach, indicating an upper limit of <4.6 kilometers(-3) for the dust density in the Pluto system.
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Affiliation(s)
- F Bagenal
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA.
| | - M Horányi
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA
| | - D J McComas
- Southwest Research Institute, San Antonio, TX 78228, USA. University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - R L McNutt
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - H A Elliott
- Southwest Research Institute, San Antonio, TX 78228, USA
| | - M E Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - L E Brown
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - P Kollmann
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S M Krimigis
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA. Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
| | - M Kusterer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C M Lisse
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D G Mitchell
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Piquette
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA
| | - A R Poppe
- Space Sciences Laboratory, University of California, Berkeley, CA 94720, USA
| | - D F Strobel
- Johns Hopkins University, Baltimore, MD 21218, USA
| | - J R Szalay
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80600, USA. Southwest Research Institute, Boulder, CO 80302, USA
| | - P Valek
- Southwest Research Institute, San Antonio, TX 78228, USA
| | - J Vandegriff
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S Weidner
- Southwest Research Institute, San Antonio, TX 78228, USA
| | - E J Zirnstein
- Southwest Research Institute, San Antonio, TX 78228, USA
| | - S A Stern
- Southwest Research Institute, Boulder, CO 80302, USA
| | - K Ennico
- NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - C B Olkin
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H A Weaver
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - L A Young
- Southwest Research Institute, Boulder, CO 80302, USA
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Bonfond B, Grodent D, Gérard JC, Radioti A, Dols V, Delamere PA, Clarke JT. The Io UV footprint: Location, inter-spot distances and tail vertical extent. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009ja014312] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- B. Bonfond
- Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liege Belgium
| | - D. Grodent
- Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liege Belgium
| | - J.-C. Gérard
- Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liege Belgium
| | - A. Radioti
- Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liege Belgium
| | - V. Dols
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - P. A. Delamere
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - J. T. Clarke
- Department of Astronomy and Center for Space Physics, Boston University; Boston Massachusetts USA
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