1
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Hansen CJ, Bolton S, Sulaiman AH, Duling S, Bagenal F, Brennan M, Connerney J, Clark G, Lunine J, Levin S, Kurth W, Mura A, Paranicas C, Tosi F, Withers P. Juno's Close Encounter With Ganymede-An Overview. Geophys Res Lett 2022; 49:e2022GL099285. [PMID: 37034391 PMCID: PMC10078441 DOI: 10.1029/2022gl099285] [Citation(s) in RCA: 1] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/20/2022] [Accepted: 05/28/2022] [Indexed: 06/19/2023]
Abstract
The Juno spacecraft has been in orbit around Jupiter since 2016. Two flybys of Ganymede were executed in 2021, opportunities realized by evolution of Juno's polar orbit over the intervening 5 years. The geometry of the close flyby just prior to the 34th perijove pass by Jupiter brought the spacecraft inside Ganymede's unique magnetosphere. Juno's payload, designed to study Jupiter's magnetosphere, had ample dynamic range to study Ganymede's magnetosphere. The Juno radio system was used both for gravity measurements and for study of Ganymede's ionosphere. Remote sensing of Ganymede returned new results on geology, surface composition, and thermal properties of the surface and subsurface.
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Affiliation(s)
| | - S. Bolton
- Southwest Research InstituteSan AntonioTXUSA
| | - A. H. Sulaiman
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | | | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
| | | | | | - G. Clark
- Johns Hopkins Applied Physics LaboratoryLaurelMDUSA
| | | | - S. Levin
- Jet Propulsion LaboratoryPasadenaCAUSA
| | - W. Kurth
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - A. Mura
- Istituto Nazionale di AstroFisica – Istituto di Astrofisica e Planetologia Spaziali (INAF‐IAPS)RomeItaly
| | - C. Paranicas
- Johns Hopkins Applied Physics LaboratoryLaurelMDUSA
| | - F. Tosi
- Istituto Nazionale di AstroFisica – Istituto di Astrofisica e Planetologia Spaziali (INAF‐IAPS)RomeItaly
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2
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Sulaiman AH, Mauk BH, Szalay JR, Allegrini F, Clark G, Gladstone GR, Kotsiaros S, Kurth WS, Bagenal F, Bonfond B, Connerney JEP, Ebert RW, Elliott SS, Gershman DJ, Hospodarsky GB, Hue V, Lysak RL, Masters A, Santolík O, Saur J, Bolton SJ. Jupiter's Low-Altitude Auroral Zones: Fields, Particles, Plasma Waves, and Density Depletions. J Geophys Res Space Phys 2022; 127:e2022JA030334. [PMID: 36247326 PMCID: PMC9539694 DOI: 10.1029/2022ja030334] [Citation(s) in RCA: 1] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 06/15/2022] [Accepted: 07/21/2022] [Indexed: 06/16/2023]
Abstract
The Juno spacecraft's polar orbits have enabled direct sampling of Jupiter's low-altitude auroral field lines. While various data sets have identified unique features over Jupiter's main aurora, they are yet to be analyzed altogether to determine how they can be reconciled and fit into the bigger picture of Jupiter's auroral generation mechanisms. Jupiter's main aurora has been classified into distinct "zones", based on repeatable signatures found in energetic electron and proton spectra. We combine fields, particles, and plasma wave data sets to analyze Zone-I and Zone-II, which are suggested to carry upward and downward field-aligned currents, respectively. We find Zone-I to have well-defined boundaries across all data sets. H+ and/or H3 + cyclotron waves are commonly observed in Zone-I in the presence of energetic upward H+ beams and downward energetic electron beams. Zone-II, on the other hand, does not have a clear poleward boundary with the polar cap, and its signatures are more sporadic. Large-amplitude solitary waves, which are reminiscent of those ubiquitous in Earth's downward current region, are a key feature of Zone-II. Alfvénic fluctuations are most prominent in the diffuse aurora and are repeatedly found to diminish in Zone-I and Zone-II, likely due to dissipation, at higher altitudes, to energize auroral electrons. Finally, we identify significant electron density depletions, by up to 2 orders of magnitude, in Zone-I, and discuss their important implications for the development of parallel potentials, Alfvénic dissipation, and radio wave generation.
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Affiliation(s)
- A. H. Sulaiman
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - B. H. Mauk
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - F. Allegrini
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - G. Clark
- Applied Physics LaboratoryJohns Hopkins UniversityLaurelMDUSA
| | - G. R. Gladstone
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - S. Kotsiaros
- DTU‐SpaceTechnical University of DenmarkKongens LyngbyDenmark
| | - W. S. Kurth
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - B. Bonfond
- Space SciencesTechnologies and Astrophysics Research InstituteLPAPUniversité de LiègeLiègeBelgium
| | - J. E. P. Connerney
- Space Research CorporationAnnapolisMDUSA
- NASA/Goddard Space Flight CenterGreenbeltMDUSA
| | - R. W. Ebert
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - S. S. Elliott
- Minnetota Institute for AstrophysicsSchool of Physics and AstronomyUniversity of MinnesotaMinneapolisMNUSA
| | | | | | - V. Hue
- Southwest Research InstituteSan AntonioTXUSA
| | - R. L. Lysak
- Minnetota Institute for AstrophysicsSchool of Physics and AstronomyUniversity of MinnesotaMinneapolisMNUSA
| | - A. Masters
- Blackett LaboratoryImperial College LondonLondonUK
| | - O. Santolík
- Department of Space PhysicsInstitute of Atmospheric Physics of the Czech Academy of SciencesPragueCzechia
- Faculty of Mathematics and PhysicsCharles UniversityPragueCzechia
| | - J. Saur
- Institute of Geophysics and MeteorologyUniversity of CologneCologneGermany
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3
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Szalay JR, Clark G, Livadiotis G, McComas DJ, Mitchell DG, Rankin JS, Sulaiman AH, Allegrini F, Bagenal F, Ebert RW, Gladstone GR, Kurth WS, Mauk BH, Valek PW, Wilson RJ, Bolton SJ. Closed Fluxtubes and Dispersive Proton Conics at Jupiter's Polar Cap. Geophys Res Lett 2022; 49:e2022GL098741. [PMID: 35859815 PMCID: PMC9285739 DOI: 10.1029/2022gl098741] [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] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/14/2022] [Accepted: 04/16/2022] [Indexed: 05/08/2023]
Abstract
Two distinct proton populations are observed over Jupiter's southern polar cap: a ∼1 keV core population and ∼1-300 keV dispersive conic population at 6-7 RJ planetocentric distance. We find the 1 keV core protons are likely the seed population for the higher-energy dispersive conics, which are accelerated from a distance of ∼3-5 RJ. Transient wave-particle heating in a "pressure-cooker" process is likely responsible for this proton acceleration. The plasma characteristics and composition during this period show Jupiter's polar-most field lines can be topologically closed, with conjugate magnetic footpoints connected to both hemispheres. Finally, these observations demonstrate energetic protons can be accelerated into Jupiter's magnetotail via wave-particle coupling.
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Affiliation(s)
- J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - G. Clark
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - G. Livadiotis
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - D. J. McComas
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - D. G. Mitchell
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - J. S. Rankin
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | | | - F. Allegrini
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - R. W. Ebert
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | | | | | - B. H. Mauk
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - P. W. Valek
- Southwest Research InstituteSan AntonioTXUSA
| | - R. J. Wilson
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
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4
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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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5
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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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6
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Kollmann P, Hill ME, Allen RC, McNutt RL, Brown LE, Barnes NP, Delamere P, Clark G, Andrews GB, Salazar N, Westlake J, Romeo G, Vandegriff J, Kusterer M, Smith D, Nelson K, Jaskulek S, Decker RB, Cheng AF, Krimigis SM, Lisse CM, Mitchell DG, Weaver HA, Elliott HA, Fattig E, Gladstone GR, Valek PW, Weidner S, Kammer J, Bagenal F, Horanyi M, Kaufmann D, Harch A, Olkin CB, Piquette MR, Spencer JR, Young LA, Ennico K, Summers ME, Stern SA. Pluto's Interaction With Energetic Heliospheric Ions. J Geophys Res Space Phys 2019; 124:7413-7424. [PMID: 35860291 PMCID: PMC9285724 DOI: 10.1029/2019ja026830] [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: 04/12/2019] [Revised: 07/08/2019] [Accepted: 07/10/2019] [Indexed: 06/15/2023]
Abstract
Pluto energies of a few kiloelectron volts and suprathermal ions with tens of kiloelectron volts and above. We measure this population using the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) instrument on board the New Horizons spacecraft that flew by Pluto in 2015. Even though the measured ions have gyroradii larger than the size of Pluto and the cross section of its magnetosphere, we find that the boundary of the magnetosphere is depleting the energetic ion intensities by about an order of magnitude close to Pluto. The intensity is increasing exponentially with distance to Pluto and reaches nominal levels of the interplanetary medium at about 190R P distance. Inside the wake of Pluto, we observe oscillations of the ion intensities with a periodicity of about 0.2 hr. We show that these can be quantitatively explained by the electric field of an ultralow-frequency wave and discuss possible physical drivers for such a field. We find no evidence for the presence of plutogenic ions in the considered energy range.
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7
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Stern SA, Weaver HA, Spencer JR, Olkin CB, Gladstone GR, Grundy WM, Moore JM, Cruikshank DP, Elliott HA, McKinnon WB, Parker JW, Verbiscer AJ, Young LA, Aguilar DA, Albers JM, Andert T, Andrews JP, Bagenal F, Banks ME, Bauer BA, Bauman JA, Bechtold KE, Beddingfield CB, Behrooz N, Beisser KB, Benecchi SD, Bernardoni E, Beyer RA, Bhaskaran S, Bierson CJ, Binzel RP, Birath EM, Bird MK, Boone DR, Bowman AF, Bray VJ, Britt DT, Brown LE, Buckley MR, Buie MW, Buratti BJ, Burke LM, Bushman SS, Carcich B, Chaikin AL, Chavez CL, Cheng AF, Colwell EJ, Conard SJ, Conner MP, Conrad CA, Cook JC, Cooper SB, Custodio OS, Dalle Ore CM, Deboy CC, Dharmavaram P, Dhingra RD, Dunn GF, Earle AM, Egan AF, Eisig J, El-Maarry MR, Engelbrecht C, Enke BL, Ercol CJ, Fattig ED, Ferrell CL, Finley TJ, Firer J, Fischetti J, Folkner WM, Fosbury MN, Fountain GH, Freeze JM, Gabasova L, Glaze LS, Green JL, Griffith GA, Guo Y, Hahn M, Hals DW, Hamilton DP, Hamilton SA, Hanley JJ, Harch A, Harmon KA, Hart HM, Hayes J, Hersman CB, Hill ME, Hill TA, Hofgartner JD, Holdridge ME, Horányi M, Hosadurga A, Howard AD, Howett CJA, Jaskulek SE, Jennings DE, Jensen JR, Jones MR, Kang HK, Katz DJ, Kaufmann DE, Kavelaars JJ, Keane JT, Keleher GP, Kinczyk M, Kochte MC, Kollmann P, Krimigis SM, Kruizinga GL, Kusnierkiewicz DY, Lahr MS, Lauer TR, Lawrence GB, Lee JE, Lessac-Chenen EJ, Linscott IR, Lisse CM, Lunsford AW, Mages DM, Mallder VA, Martin NP, May BH, McComas DJ, McNutt RL, Mehoke DS, Mehoke TS, Nelson DS, Nguyen HD, Núñez JI, Ocampo AC, Owen WM, Oxton GK, Parker AH, Pätzold M, Pelgrift JY, Pelletier FJ, Pineau JP, Piquette MR, Porter SB, Protopapa S, Quirico E, Redfern JA, Regiec AL, Reitsema HJ, Reuter DC, Richardson DC, Riedel JE, Ritterbush MA, Robbins SJ, Rodgers DJ, Rogers GD, Rose DM, Rosendall PE, Runyon KD, Ryschkewitsch MG, Saina MM, Salinas MJ, Schenk PM, Scherrer JR, Schlei WR, Schmitt B, Schultz DJ, Schurr DC, Scipioni F, Sepan RL, Shelton RG, Showalter MR, Simon M, Singer KN, Stahlheber EW, Stanbridge DR, Stansberry JA, Steffl AJ, Strobel DF, Stothoff MM, Stryk T, Stuart JR, Summers ME, Tapley MB, Taylor A, Taylor HW, Tedford RM, Throop HB, Turner LS, Umurhan OM, Van Eck J, Velez D, Versteeg MH, Vincent MA, Webbert RW, Weidner SE, Weigle GE, Wendel JR, White OL, Whittenburg KE, Williams BG, Williams KE, Williams SP, Winters HL, Zangari AM, Zurbuchen TH. Initial results from the New Horizons exploration of 2014 MU 69, a small Kuiper Belt object. Science 2019; 364:364/6441/eaaw9771. [PMID: 31097641 DOI: 10.1126/science.aaw9771] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/16/2019] [Indexed: 11/02/2022]
Abstract
The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.
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Affiliation(s)
- S A Stern
- Southwest Research Institute, Boulder, CO 80302, USA.
| | - H A Weaver
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J R Spencer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - C B Olkin
- Southwest Research Institute, Boulder, CO 80302, USA
| | - G R Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - W M Grundy
- Lowell Observatory, Flagstaff, AZ 86001, USA
| | - J M Moore
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - D P Cruikshank
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - H A Elliott
- Southwest Research Institute, San Antonio, TX 78238, USA.,Department of Physics and Astronomy, University of Texas, San Antonio, TX 78249, USA
| | - W B McKinnon
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University, St. Louis, MO 63130, USA
| | - J Wm Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - A J Verbiscer
- Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA
| | - L A Young
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D A Aguilar
- Independent consultant, Carbondale, CO 81623, USA
| | - J M Albers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T Andert
- Universität der Bundeswehr München, Neubiberg 85577, Germany
| | - J P Andrews
- Southwest Research Institute, Boulder, CO 80302, USA
| | - F Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - M E Banks
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - B A Bauer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - K E Bechtold
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C B Beddingfield
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - N Behrooz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K B Beisser
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S D Benecchi
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - E Bernardoni
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - R A Beyer
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - S Bhaskaran
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - C J Bierson
- Earth and Planetary Science Department, University of California, Santa Cruz, CA 95064, USA
| | - R P Binzel
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - E M Birath
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M K Bird
- Argelander-Institut für Astronomie, University of Bonn, Bonn D-53121, Germany.,Rheinisches Institut für Umweltforschung, Universität zu Köln, Cologne 50931, Germany
| | - D R Boone
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - A F Bowman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - V J Bray
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
| | - D T Britt
- Department of Physics, University of Central Florida, Orlando, FL 32816, USA
| | - L E Brown
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M R Buckley
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M W Buie
- Southwest Research Institute, Boulder, CO 80302, USA
| | - B J Buratti
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - L M Burke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S S Bushman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B Carcich
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.,Cornell University, Ithaca, NY 14853, USA
| | - A L Chaikin
- Independent science writer, Arlington, VT 05250, USA
| | - C L Chavez
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - A F Cheng
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E J Colwell
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S J Conard
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M P Conner
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C A Conrad
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J C Cook
- Pinhead Institute, Telluride, CO 81435, USA
| | - S B Cooper
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - O S Custodio
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C M Dalle Ore
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - C C Deboy
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - P Dharmavaram
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - G F Dunn
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - A M Earle
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - A F Egan
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J Eisig
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M R El-Maarry
- Department of Earth and Planetary Sciences, Birkbeck, University of London, London WC1E 7HX, UK
| | - C Engelbrecht
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B L Enke
- Southwest Research Institute, Boulder, CO 80302, USA
| | - C J Ercol
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E D Fattig
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - C L Ferrell
- Southwest Research Institute, Boulder, CO 80302, USA
| | - T J Finley
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J Firer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - W M Folkner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M N Fosbury
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - G H Fountain
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J M Freeze
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - L Gabasova
- University Grenoble Alpes, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, 38000 Grenoble, France
| | - L S Glaze
- NASA Headquarters, Washington, DC 20546, USA
| | - J L Green
- NASA Headquarters, Washington, DC 20546, USA
| | - G A Griffith
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - Y Guo
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Hahn
- Rheinisches Institut für Umweltforschung, Universität zu Köln, Cologne 50931, Germany
| | - D W Hals
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D P Hamilton
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - S A Hamilton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J J Hanley
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - A Harch
- Cornell University, Ithaca, NY 14853, USA
| | - K A Harmon
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - H M Hart
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J Hayes
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C B Hersman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M E Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T A Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J D Hofgartner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M E Holdridge
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Horányi
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - A Hosadurga
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A D Howard
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
| | - C J A Howett
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S E Jaskulek
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D E Jennings
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J R Jensen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M R Jones
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - H K Kang
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D J Katz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D E Kaufmann
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J J Kavelaars
- National Research Council of Canada, Victoria, BC V9E 2E7, Canada
| | - J T Keane
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - G P Keleher
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Kinczyk
- Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - M C Kochte
- 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
| | - G L Kruizinga
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - D Y Kusnierkiewicz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M S Lahr
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T R Lauer
- National Optical Astronomy Observatory, Tucson, AZ 26732, USA
| | - G B Lawrence
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J E Lee
- NASA Marshall Space Flight Center, Huntsville, AL 35812, USA
| | | | - I R Linscott
- Independent consultant, Mountain View, CA 94043, USA
| | - C M Lisse
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A W Lunsford
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D M Mages
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - V A Mallder
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - N P Martin
- Independent consultant, Crested Butte, CO 81224, USA
| | - B H May
- Independent collaborator, Windlesham GU20 6YW, UK
| | - D J McComas
- Southwest Research Institute, San Antonio, TX 78238, USA.,Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
| | - R L McNutt
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D S Mehoke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T S Mehoke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - H D Nguyen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J I Núñez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A C Ocampo
- NASA Headquarters, Washington, DC 20546, USA
| | - W M Owen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - G K Oxton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A H Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M Pätzold
- Rheinisches Institut für Umweltforschung, Universität zu Köln, Cologne 50931, Germany
| | | | | | - J P Pineau
- Stellar Solutions, Palo Alto, CA 94306, USA
| | - M R Piquette
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - S B Porter
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S Protopapa
- Southwest Research Institute, Boulder, CO 80302, USA
| | - E Quirico
- University Grenoble Alpes, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, 38000 Grenoble, France
| | - J A Redfern
- Southwest Research Institute, Boulder, CO 80302, USA
| | - A L Regiec
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - D C Reuter
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D C Richardson
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - J E Riedel
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M A Ritterbush
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - S J Robbins
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D J Rodgers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - G D Rogers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D M Rose
- Southwest Research Institute, Boulder, CO 80302, USA
| | - P E Rosendall
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K D Runyon
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M G Ryschkewitsch
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M M Saina
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - P M Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - J R Scherrer
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - W R Schlei
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B Schmitt
- University Grenoble Alpes, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, 38000 Grenoble, France
| | - D J Schultz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D C Schurr
- NASA Headquarters, Washington, DC 20546, USA
| | - F Scipioni
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - R L Sepan
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - R G Shelton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - M Simon
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K N Singer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - E W Stahlheber
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - J A Stansberry
- Space Telescope Science Institute, Baltimore, MD 21218, USA
| | - A J Steffl
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D F Strobel
- Johns Hopkins University, Baltimore, MD 21218, USA
| | - M M Stothoff
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - T Stryk
- Roane State Community College, Oak Ridge, TN 37830, USA
| | - J R Stuart
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M E Summers
- George Mason University, Fairfax, VA 22030, USA
| | - M B Tapley
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - A Taylor
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - H W Taylor
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - R M Tedford
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H B Throop
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - L S Turner
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - O M Umurhan
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - J Van Eck
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D Velez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M H Versteeg
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - M A Vincent
- Southwest Research Institute, Boulder, CO 80302, USA
| | - R W Webbert
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S E Weidner
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
| | - G E Weigle
- Independent consultant, Burden, KS 67019, USA
| | - J R Wendel
- NASA Headquarters, Washington, DC 20546, USA
| | - O L White
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - K E Whittenburg
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | | | - S P Williams
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - H L Winters
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A M Zangari
- Southwest Research Institute, Boulder, CO 80302, USA
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8
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Ebert RW, Greathouse TK, Clark G, Allegrini F, Bagenal F, Bolton SJ, Connerney JEP, Gladstone GR, Imai M, Hue V, Kurth WS, Levin S, Louarn P, Mauk BH, McComas DJ, Paranicas C, Szalay JR, Thomsen MF, Valek PW, Wilson RJ. Comparing Electron Energetics and UV Brightness in Jupiter's Northern Polar Region During Juno Perijove 5. Geophys Res Lett 2019; 46:19-27. [PMID: 30828110 PMCID: PMC6378591 DOI: 10.1029/2018gl081129] [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: 10/29/2018] [Revised: 12/14/2018] [Accepted: 12/20/2018] [Indexed: 05/24/2023]
Abstract
We compare electron and UV observations mapping to the same location in Jupiter's northern polar region, poleward of the main aurora, during Juno perijove 5. Simultaneous peaks in UV brightness and electron energy flux are identified when observations map to the same location at the same time. The downward energy flux during these simultaneous observations was not sufficient to generate the observed UV brightness; the upward energy flux was. We propose that the primary acceleration region is below Juno's altitude, from which the more intense upward electrons originate. For the complete interval, the UV brightness peaked at ~240 kilorayleigh (kR); the downward and upward energy fluxes peaked at 60 and 700 mW/m2, respectively. Increased downward energy fluxes are associated with increased contributions from tens of keV electrons. These observations provide evidence that bidirectional electron beams with broad energy distributions can produce tens to hundreds of kilorayleigh polar UV emissions.
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Affiliation(s)
- R. W. Ebert
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | | | - G. Clark
- Johns Hopkins University Applied Physics LabLaurelMDUSA
| | - F. Allegrini
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | | | | | - G. R. Gladstone
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - M. Imai
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - V. Hue
- Southwest Research InstituteSan AntonioTXUSA
| | - W. S. Kurth
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | - S. Levin
- Jet Propulsion LaboratoryPasadenaCAUSA
| | - P. Louarn
- Institut de Recherche en Astrophysique et PlanétologieToulouseFrance
| | - B. H. Mauk
- Johns Hopkins University Applied Physics LabLaurelMDUSA
| | - D. J. McComas
- Southwest Research InstituteSan AntonioTXUSA
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - C. Paranicas
- Johns Hopkins University Applied Physics LabLaurelMDUSA
| | - J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | | | - P. W. Valek
- Southwest Research InstituteSan AntonioTXUSA
| | - R. J. Wilson
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
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9
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Ebert RW, Greathouse TK, Clark G, Allegrini F, Bagenal F, Bolton SJ, Connerney JEP, Gladstone GR, Imai M, Hue V, Kurth WS, Levin S, Louarn P, Mauk BH, McComas DJ, Paranicas C, Szalay JR, Thomsen MF, Valek PW, Wilson RJ. Comparing Electron Energetics and UV Brightness in Jupiter's Northern Polar Region During Juno Perijove 5. Geophys Res Lett 2019; 46:19-27. [PMID: 30828110 DOI: 10.1029/2019gl084146] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/14/2018] [Accepted: 12/20/2018] [Indexed: 05/24/2023]
Abstract
We compare electron and UV observations mapping to the same location in Jupiter's northern polar region, poleward of the main aurora, during Juno perijove 5. Simultaneous peaks in UV brightness and electron energy flux are identified when observations map to the same location at the same time. The downward energy flux during these simultaneous observations was not sufficient to generate the observed UV brightness; the upward energy flux was. We propose that the primary acceleration region is below Juno's altitude, from which the more intense upward electrons originate. For the complete interval, the UV brightness peaked at ~240 kilorayleigh (kR); the downward and upward energy fluxes peaked at 60 and 700 mW/m2, respectively. Increased downward energy fluxes are associated with increased contributions from tens of keV electrons. These observations provide evidence that bidirectional electron beams with broad energy distributions can produce tens to hundreds of kilorayleigh polar UV emissions.
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Affiliation(s)
- R W Ebert
- Southwest Research Institute San Antonio TX USA
- Department of Physics and Astronomy University of Texas at San Antonio San Antonio TX USA
| | | | - G Clark
- Johns Hopkins University Applied Physics Lab Laurel MD USA
| | - F Allegrini
- Southwest Research Institute San Antonio TX USA
- Department of Physics and Astronomy University of Texas at San Antonio San Antonio TX USA
| | - F Bagenal
- Laboratory for Atmospheric and Space Physics University of Colorado Boulder Boulder CO USA
| | - S J Bolton
- Southwest Research Institute San Antonio TX USA
| | | | - G R Gladstone
- Southwest Research Institute San Antonio TX USA
- Department of Physics and Astronomy University of Texas at San Antonio San Antonio TX USA
| | - M Imai
- Department of Physics and Astronomy University of Iowa Iowa City IA USA
| | - V Hue
- Southwest Research Institute San Antonio TX USA
| | - W S Kurth
- Department of Physics and Astronomy University of Iowa Iowa City IA USA
| | - S Levin
- Jet Propulsion Laboratory Pasadena CA USA
| | - P Louarn
- Institut de Recherche en Astrophysique et Planétologie Toulouse France
| | - B H Mauk
- Johns Hopkins University Applied Physics Lab Laurel MD USA
| | - D J McComas
- Southwest Research Institute San Antonio TX USA
- Department of Astrophysical Sciences Princeton University Princeton NJ USA
| | - C Paranicas
- Johns Hopkins University Applied Physics Lab Laurel MD USA
| | - J R Szalay
- Department of Astrophysical Sciences Princeton University Princeton NJ USA
| | | | - P W Valek
- Southwest Research Institute San Antonio TX USA
| | - R J Wilson
- Laboratory for Atmospheric and Space Physics University of Colorado Boulder Boulder CO USA
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10
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Mura A, Adriani A, Connerney JEP, Bolton S, Altieri F, Bagenal F, Bonfond B, Dinelli BM, Gérard JC, Greathouse T, Grodent D, Levin S, Mauk B, Moriconi ML, Saur J, Waite JH, Amoroso M, Cicchetti A, Fabiano F, Filacchione G, Grassi D, Migliorini A, Noschese R, Olivieri A, Piccioni G, Plainaki C, Sindoni G, Sordini R, Tosi F, Turrini D. Juno observations of spot structures and a split tail in Io-induced aurorae on Jupiter. Science 2018; 361:774-777. [PMID: 29976795 DOI: 10.1126/science.aat1450] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/15/2018] [Indexed: 11/02/2022]
Abstract
Jupiter's aurorae are produced in its upper atmosphere when incoming high-energy electrons precipitate along the planet's magnetic field lines. A northern and a southern main auroral oval are visible, surrounded by small emission features associated with the Galilean moons. We present infrared observations, obtained with the Juno spacecraft, showing that in the case of Io, this emission exhibits a swirling pattern that is similar in appearance to a von Kármán vortex street. Well downstream of the main auroral spots, the extended tail is split in two. Both of Ganymede's footprints also appear as a pair of emission features, which may provide a remote measure of Ganymede's magnetosphere. These features suggest that the magnetohydrodynamic interaction between Jupiter and its moon is more complex than previously anticipated.
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Affiliation(s)
- A Mura
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy.
| | - A Adriani
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - J E P Connerney
- Space Research Corporation, Annapolis, MD, USA.,NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - S Bolton
- Southwest Research Institute, San Antonio, TX, USA
| | - F Altieri
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - F Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO, USA
| | - B Bonfond
- Space Science, Technologies and Astrophysical Research Institute, Laboratory for Planetary and Atmospheric Physics, University of Liège, Liège, Belgium
| | - B M Dinelli
- Institute of Atmospheric Sciences and Climate, National Research Council, Italy
| | - J-C Gérard
- Space Science, Technologies and Astrophysical Research Institute, Laboratory for Planetary and Atmospheric Physics, University of Liège, Liège, Belgium
| | - T Greathouse
- Southwest Research Institute, San Antonio, TX, USA
| | - D Grodent
- Space Science, Technologies and Astrophysical Research Institute, Laboratory for Planetary and Atmospheric Physics, University of Liège, Liège, Belgium
| | - S Levin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - B Mauk
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD, USA
| | - M L Moriconi
- Institute of Atmospheric Sciences and Climate, National Research Council, Italy
| | - J Saur
- Institut für Geophysik und Meteorologie, University of Cologne, Köln, Germany
| | - J H Waite
- Southwest Research Institute, San Antonio, TX, USA.,Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
| | - M Amoroso
- Agenzia Spaziale Italiana, Rome, Italy
| | - A Cicchetti
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - F Fabiano
- Institute of Atmospheric Sciences and Climate, National Research Council, Italy
| | - G Filacchione
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - D Grassi
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - A Migliorini
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - R Noschese
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | | | - G Piccioni
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - C Plainaki
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy.,Agenzia Spaziale Italiana, Rome, Italy
| | - G Sindoni
- Agenzia Spaziale Italiana, Rome, Italy
| | - R Sordini
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - F Tosi
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
| | - D Turrini
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, Italy
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11
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Connerney JEP, Adriani A, Allegrini F, Bagenal F, Bolton SJ, Bonfond B, Cowley SWH, Gerard JC, Gladstone GR, Grodent D, Hospodarsky G, Jorgensen JL, Kurth WS, Levin SM, Mauk B, McComas DJ, Mura A, Paranicas C, Smith EJ, Thorne RM, Valek P, Waite J. Jupiter's magnetosphere and aurorae observed by the Juno spacecraft during its first polar orbits. Science 2018; 356:826-832. [PMID: 28546207 DOI: 10.1126/science.aam5928] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 04/20/2017] [Indexed: 11/02/2022]
Abstract
The Juno spacecraft acquired direct observations of the jovian magnetosphere and auroral emissions from a vantage point above the poles. Juno's capture orbit spanned the jovian magnetosphere from bow shock to the planet, providing magnetic field, charged particle, and wave phenomena context for Juno's passage over the poles and traverse of Jupiter's hazardous inner radiation belts. Juno's energetic particle and plasma detectors measured electrons precipitating in the polar regions, exciting intense aurorae, observed simultaneously by the ultraviolet and infrared imaging spectrographs. Juno transited beneath the most intense parts of the radiation belts, passed about 4000 kilometers above the cloud tops at closest approach, well inside the jovian rings, and recorded the electrical signatures of high-velocity impacts with small particles as it traversed the equator.
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Affiliation(s)
- J E P Connerney
- Space Research Corporation, Annapolis, MD 21403, USA. .,NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - A Adriani
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, 00133, Italy
| | - F Allegrini
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - F Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - S J Bolton
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - B Bonfond
- Institut d'Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium
| | | | - J-C Gerard
- Institut d'Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium
| | - G R Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - D Grodent
- Institut d'Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium
| | | | - J L Jorgensen
- National Space Institute, Technical University of Denmark, Kongens Lyngby, 2800, Denmark
| | - W S Kurth
- University of Iowa, Iowa City, IA 52242, USA
| | - S M Levin
- Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109, USA
| | - B Mauk
- Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D J McComas
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
| | - A Mura
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, 00133, Italy
| | - C Paranicas
- Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E J Smith
- Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109, USA
| | - R M Thorne
- Department of Atmospheric and Oceanic Sciences, University of California-Los Angeles, Los Angeles, CA 90095, USA
| | - P Valek
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - J Waite
- Southwest Research Institute, San Antonio, TX 78238, USA
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12
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Gladstone GR, Versteeg MH, Greathouse TK, Hue V, Davis MW, Gérard J, Grodent DC, Bonfond B, Nichols JD, Wilson RJ, Hospodarsky GB, Bolton SJ, Levin SM, Connerney JEP, Adriani A, Kurth WS, Mauk BH, Valek P, McComas DJ, Orton GS, Bagenal F. Juno-UVS approach observations of Jupiter's auroras. Geophys Res Lett 2017; 44:7668-7675. [PMID: 28989207 PMCID: PMC5606505 DOI: 10.1002/2017gl073377] [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: 03/07/2017] [Revised: 04/17/2017] [Accepted: 04/18/2017] [Indexed: 06/07/2023]
Abstract
Juno ultraviolet spectrograph (UVS) observations of Jupiter's aurora obtained during approach are presented. Prior to the bow shock crossing on 24 June 2016, the Juno approach provided a rare opportunity to correlate local solar wind conditions with Jovian auroral emissions. Some of Jupiter's auroral emissions are expected to be controlled or modified by local solar wind conditions. Here we compare synoptic Juno-UVS observations of Jupiter's auroral emissions, acquired during 3-29 June 2016, with in situ solar wind observations, and related Jupiter observations from Earth. Four large auroral brightening events are evident in the synoptic data, in which the total emitted auroral power increases by a factor of 3-4 for a few hours. Only one of these brightening events correlates well with large transient increases in solar wind ram pressure. The brightening events which are not associated with the solar wind generally have a risetime of ~2 h and a decay time of ~5 h.
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Affiliation(s)
- G. R. Gladstone
- Southwest Research InstituteSan AntonioTexasUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTexasUSA
| | | | | | - V. Hue
- Southwest Research InstituteSan AntonioTexasUSA
| | - M. W. Davis
- Southwest Research InstituteSan AntonioTexasUSA
| | - J.‐C. Gérard
- STAR Institute, LPAPUniversité de LiègeLiègeBelgium
| | | | - B. Bonfond
- STAR Institute, LPAPUniversité de LiègeLiègeBelgium
| | - J. D. Nichols
- Department of Physics and AstronomyUniversity of LeicesterLeicesterUK
| | - R. J. Wilson
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderColoradoUSA
| | - G. B. Hospodarsky
- Department of Physics and AstronomyUniversity of IowaIowa CityIowaUSA
| | | | - S. M. Levin
- Jet Propulsion LaboratoryPasadenaCaliforniaUSA
| | | | - A. Adriani
- Istituto di Astrofisica e Planetologia SpazialiRomeItaly
| | - W. S. Kurth
- Department of Physics and AstronomyUniversity of IowaIowa CityIowaUSA
| | - B. H. Mauk
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - P. Valek
- Southwest Research InstituteSan AntonioTexasUSA
| | - D. J. McComas
- Office of the VP for PPPL and Department of Astrophysical SciencesPrinceton UniversityPrincetonNew JerseyUSA
| | - G. S. Orton
- Jet Propulsion LaboratoryPasadenaCaliforniaUSA
| | - F. Bagenal
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderColoradoUSA
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13
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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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14
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Gladstone GR, Stern SA, Ennico K, Olkin CB, Weaver HA, Young LA, Summers ME, Strobel DF, Hinson DP, Kammer JA, Parker AH, Steffl AJ, Linscott IR, Parker JW, Cheng AF, Slater DC, Versteeg MH, Greathouse TK, Retherford KD, Throop H, Cunningham NJ, Woods WW, Singer KN, Tsang CCC, Schindhelm E, Lisse CM, Wong ML, Yung YL, Zhu X, Curdt W, Lavvas P, Young EF, Tyler GL, Bagenal F, Grundy WM, McKinnon WB, Moore JM, Spencer JR, Andert T, Andrews J, Banks M, Bauer B, Bauman J, Barnouin OS, Bedini P, Beisser K, Beyer RA, Bhaskaran S, Binzel RP, Birath E, Bird M, Bogan DJ, Bowman A, Bray VJ, Brozovic M, Bryan C, Buckley MR, Buie MW, Buratti BJ, Bushman SS, Calloway A, Carcich B, Conard S, Conrad CA, Cook JC, Cruikshank DP, Custodio OS, Ore CMD, Deboy C, Dischner ZJB, Dumont P, Earle AM, Elliott HA, Ercol J, Ernst CM, Finley T, Flanigan SH, Fountain G, Freeze MJ, Green JL, Guo Y, Hahn M, Hamilton DP, Hamilton SA, Hanley J, Harch A, Hart HM, Hersman CB, Hill A, Hill ME, Holdridge ME, Horanyi M, Howard AD, Howett CJA, Jackman C, Jacobson RA, Jennings DE, Kang HK, Kaufmann DE, Kollmann P, Krimigis SM, Kusnierkiewicz D, Lauer TR, Lee JE, Lindstrom KL, Lunsford AW, Mallder VA, Martin N, McComas DJ, McNutt RL, Mehoke D, Mehoke T, Melin ED, Mutchler M, Nelson D, Nimmo F, Nunez JI, Ocampo A, Owen WM, Paetzold M, Page B, Pelletier F, Peterson J, Pinkine N, Piquette M, Porter SB, Protopapa S, Redfern J, Reitsema HJ, Reuter DC, Roberts JH, Robbins SJ, Rogers G, Rose D, Runyon K, Ryschkewitsch MG, Schenk P, Sepan B, Showalter MR, Soluri M, Stanbridge D, Stryk T, Szalay JR, Tapley M, Taylor A, Taylor H, Umurhan OM, Verbiscer AJ, Versteeg MH, Vincent M, Webbert R, Weidner S, Weigle GE, White OL, Whittenburg K, Williams BG, Williams K, Williams S, Zangari AM, Zirnstein E. The atmosphere of Pluto as observed by New Horizons. Science 2016; 351:aad8866. [PMID: 26989258 DOI: 10.1126/science.aad8866] [Citation(s) in RCA: 179] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- G. Randall Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
- University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - S. Alan Stern
- Southwest Research Institute, Boulder, CO 80302, USA
| | - Kimberly Ennico
- National Aeronautics and Space Administration, Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | | | - Harold A. Weaver
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | | | | | - David P. Hinson
- Search for Extraterrestrial Intelligence Institute, Mountain View, CA 94043, USA
| | | | | | | | | | | | - Andrew F. Cheng
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | | | | | - Kurt D. Retherford
- Southwest Research Institute, San Antonio, TX 78238, USA
- University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Henry Throop
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | | | | | | | | | | | - Carey M. Lisse
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - Yuk L. Yung
- California Institute of Technology, Pasadena, CA 91125, USA
| | - Xun Zhu
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - Werner Curdt
- Max-Planck-Institut für Sonnensystemforschung, 37191 Katlenburg-Lindau, Germany
| | - Panayotis Lavvas
- Groupe de Spectroscopie Moléculaire et Atmosphérique, Université Reims Champagne-Ardenne, 51687 Reims, France
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15
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Stern SA, Bagenal F, Ennico K, Gladstone GR, Grundy WM, McKinnon WB, Moore JM, Olkin CB, Spencer JR, Weaver HA, Young LA, Andert T, Andrews J, Banks M, Bauer B, Bauman J, Barnouin OS, Bedini P, Beisser K, Beyer RA, Bhaskaran S, Binzel RP, Birath E, Bird M, Bogan DJ, Bowman A, Bray VJ, Brozovic M, Bryan C, Buckley MR, Buie MW, Buratti BJ, Bushman SS, Calloway A, Carcich B, Cheng AF, Conard S, Conrad CA, Cook JC, Cruikshank DP, Custodio OS, Dalle Ore CM, Deboy C, Dischner ZJB, Dumont P, Earle AM, Elliott HA, Ercol J, Ernst CM, Finley T, Flanigan SH, Fountain G, Freeze MJ, Greathouse T, Green JL, Guo Y, Hahn M, Hamilton DP, Hamilton SA, Hanley J, Harch A, Hart HM, Hersman CB, Hill A, Hill ME, Hinson DP, Holdridge ME, Horanyi M, Howard AD, Howett CJA, Jackman C, Jacobson RA, Jennings DE, Kammer JA, Kang HK, Kaufmann DE, Kollmann P, Krimigis SM, Kusnierkiewicz D, Lauer TR, Lee JE, Lindstrom KL, Linscott IR, Lisse CM, Lunsford AW, Mallder VA, Martin N, McComas DJ, McNutt RL, Mehoke D, Mehoke T, Melin ED, Mutchler M, Nelson D, Nimmo F, Nunez JI, Ocampo A, Owen WM, Paetzold M, Page B, Parker AH, Parker JW, Pelletier F, Peterson J, Pinkine N, Piquette M, Porter SB, Protopapa S, Redfern J, Reitsema HJ, Reuter DC, Roberts JH, Robbins SJ, Rogers G, Rose D, Runyon K, Retherford KD, Ryschkewitsch MG, Schenk P, Schindhelm E, Sepan B, Showalter MR, Singer KN, Soluri M, Stanbridge D, Steffl AJ, Strobel DF, Stryk T, Summers ME, Szalay JR, Tapley M, Taylor A, Taylor H, Throop HB, Tsang CCC, Tyler GL, Umurhan OM, Verbiscer AJ, Versteeg MH, Vincent M, Webbert R, Weidner S, Weigle GE, White OL, Whittenburg K, Williams BG, Williams K, Williams S, Woods WW, Zangari AM, Zirnstein E. The Pluto system: Initial results from its exploration by New Horizons. Science 2015; 350:aad1815. [DOI: 10.1126/science.aad1815] [Citation(s) in RCA: 367] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- S. A. Stern
- Southwest Research Institute, Boulder, CO 80302, USA
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - K. Ennico
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | | | | | - W. B. McKinnon
- Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, USA
| | - J. M. Moore
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - C. B. Olkin
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J. R. Spencer
- 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
| | - T. Andert
- Universität der Bundeswehr München, Neubiberg 85577, Germany
| | - J. Andrews
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M. Banks
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - B. Bauer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J. Bauman
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - O. S. Barnouin
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - P. Bedini
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K. Beisser
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - R. A. Beyer
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - S. Bhaskaran
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - R. P. Binzel
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - E. Birath
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M. Bird
- University of Bonn, Bonn D-53113, Germany
| | - D. J. Bogan
- NASA Headquarters (retired), Washington, DC 20546, USA
| | - A. Bowman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - V. J. Bray
- University of Arizona, Tucson, AZ 85721, USA
| | - M. Brozovic
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - C. Bryan
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - M. R. Buckley
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. W. Buie
- Southwest Research Institute, Boulder, CO 80302, USA
| | - B. J. Buratti
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - S. S. Bushman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A. Calloway
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B. Carcich
- Cornell University, Ithaca, NY 14853, USA
| | - A. F. Cheng
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S. Conard
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C. A. Conrad
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J. C. Cook
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D. P. Cruikshank
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - O. S. Custodio
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C. M. Dalle Ore
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - C. Deboy
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - P. Dumont
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - A. M. Earle
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - H. A. Elliott
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - J. Ercol
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C. M. Ernst
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T. Finley
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S. H. Flanigan
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - G. Fountain
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. J. Freeze
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T. Greathouse
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - J. L. Green
- NASA Headquarters, Washington, DC 20546, USA
| | - Y. Guo
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. Hahn
- Rheinisches Institut für Umweltforschung an der Universität zu Köln, Cologne 50931, Germany
| | - D. P. Hamilton
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - S. A. Hamilton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J. Hanley
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - A. Harch
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H. M. Hart
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C. B. Hersman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A. Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. E. Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D. P. Hinson
- Search for Extraterrestrial Intelligence Institute, Mountain View, CA 94043, USA
| | - M. E. Holdridge
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. Horanyi
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - A. D. Howard
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
| | | | | | - R. A. Jacobson
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - D. E. Jennings
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J. A. Kammer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H. K. Kang
- 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
| | - D. Kusnierkiewicz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T. R. Lauer
- National Optical Astronomy Observatory, Tucson, AZ 26732, USA
| | - J. E. Lee
- NASA Marshall Space Flight Center, Huntsville, AL 35812, USA
| | - K. L. Lindstrom
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - C. M. Lisse
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A. W. Lunsford
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - V. A. Mallder
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - N. Martin
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D. J. McComas
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - R. L. McNutt
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D. Mehoke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T. Mehoke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E. D. Melin
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. Mutchler
- Space Telescope Science Institute, Baltimore, MD 21218, USA
| | - D. Nelson
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - F. Nimmo
- University of California, Santa Cruz, CA 95064, USA
| | - J. I. Nunez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A. Ocampo
- NASA Headquarters, Washington, DC 20546, USA
| | - W. M. Owen
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - M. Paetzold
- Rheinisches Institut für Umweltforschung an der Universität zu Köln, Cologne 50931, Germany
| | - B. Page
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - A. H. Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J. W. Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | | | - J. Peterson
- Southwest Research Institute, Boulder, CO 80302, USA
| | - N. Pinkine
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. Piquette
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - S. B. Porter
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S. Protopapa
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - J. Redfern
- Southwest Research Institute, Boulder, CO 80302, USA
| | | | - D. C. Reuter
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J. H. Roberts
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S. J. Robbins
- Southwest Research Institute, Boulder, CO 80302, USA
| | - G. Rogers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D. Rose
- Southwest Research Institute, Boulder, CO 80302, USA
| | - K. Runyon
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | | | - P. Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - E. Schindhelm
- Southwest Research Institute, Boulder, CO 80302, USA
| | - B. Sepan
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M. R. Showalter
- Search for Extraterrestrial Intelligence Institute, Mountain View, CA 94043, USA
| | - K. N. Singer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M. Soluri
- Michael Soluri Photography, New York, NY 10014, USA
| | | | - A. J. Steffl
- Southwest Research Institute, Boulder, CO 80302, USA
| | | | - T. Stryk
- Roane State Community College, Jamestown, TN 38556, USA
| | | | - J. R. Szalay
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - M. Tapley
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - A. Taylor
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - H. Taylor
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - H. B. Throop
- Planetary Science Institute, Tucson, AZ 85719, USA
| | | | - G. L. Tyler
- Stanford University, Stanford, CA 94305, USA
| | - O. M. Umurhan
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - A. J. Verbiscer
- Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA
| | - M. H. Versteeg
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - M. Vincent
- Southwest Research Institute, Boulder, CO 80302, USA
| | - R. Webbert
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S. Weidner
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - G. E. Weigle
- Southwest Research Institute, San Antonio, TX 28510, USA
| | - O. L. White
- National Aeronautics and Space Administration (NASA) Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - K. Whittenburg
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | | | - S. Williams
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - W. W. Woods
- Stanford University, Stanford, CA 94305, USA
| | - A. M. Zangari
- Southwest Research Institute, Boulder, CO 80302, USA
| | - E. Zirnstein
- Southwest Research Institute, San Antonio, TX 28510, USA
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Pappalardo RT, Vance S, Bagenal F, Bills BG, Blaney DL, Blankenship DD, Brinckerhoff WB, Connerney JEP, Hand KP, Hoehler TM, Leisner JS, Kurth WS, McGrath MA, Mellon MT, Moore JM, Patterson GW, Prockter LM, Senske DA, Schmidt BE, Shock EL, Smith DE, Soderlund KM. Science potential from a Europa lander. Astrobiology 2013; 13:740-773. [PMID: 23924246 DOI: 10.1089/ast.2013.1003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The prospect of a future soft landing on the surface of Europa is enticing, as it would create science opportunities that could not be achieved through flyby or orbital remote sensing, with direct relevance to Europa's potential habitability. Here, we summarize the science of a Europa lander concept, as developed by our NASA-commissioned Science Definition Team. The science concept concentrates on observations that can best be achieved by in situ examination of Europa from its surface. We discuss the suggested science objectives and investigations for a Europa lander mission, along with a model planning payload of instruments that could address these objectives. The highest priority is active sampling of Europa's non-ice material from at least two different depths (0.5-2 cm and 5-10 cm) to understand its detailed composition and chemistry and the specific nature of salts, any organic materials, and other contaminants. A secondary focus is geophysical prospecting of Europa, through seismology and magnetometry, to probe the satellite's ice shell and ocean. Finally, the surface geology can be characterized in situ at a human scale. A Europa lander could take advantage of the complex radiation environment of the satellite, landing where modeling suggests that radiation is about an order of magnitude less intense than in other regions. However, to choose a landing site that is safe and would yield the maximum science return, thorough reconnaissance of Europa would be required prior to selecting a scientifically optimized landing site.
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Affiliation(s)
- R T Pappalardo
- Planetary Sciences Section, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
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Desroche M, Bagenal F, Delamere PA, Erkaev N. Conditions at the expanded Jovian magnetopause and implications for the solar wind interaction. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012ja017621] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fleshman BL, Delamere PA, Bagenal F, Cassidy T. The roles of charge exchange and dissociation in spreading Saturn's neutral clouds. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003996] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wilson RJ, Delamere PA, Bagenal F, Masters A. Kelvin-Helmholtz instability at Saturn's magnetopause: Cassini ion data analysis. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011ja016723] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Affiliation(s)
- P. A. Delamere
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
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Ray LC, Ergun RE, Delamere PA, Bagenal F. Magnetosphere-ionosphere coupling at Jupiter: Effect of field-aligned potentials on angular momentum transport. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010ja015423] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [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)
- L. C. Ray
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | - P. A. Delamere
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
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Ergun RE, Ray L, Delamere PA, Bagenal F, Dols V, Su YJ. Generation of parallel electric fields in the Jupiter-Io torus wake region. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008ja013968] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [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)
- R. E. Ergun
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - L. Ray
- 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
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - V. Dols
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - Y.-J. Su
- Department of Physics; University of Texas at Arlington; Arlington Texas USA
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Affiliation(s)
- L. C. Ray
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - Y.-J. Su
- Department of Physics; University of Texas at Arlington; Arlington Texas USA
| | - R. E. Ergun
- 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
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
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26
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Affiliation(s)
- 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
| | - F. Bagenal
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
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McComas DJ, Allegrini F, Bagenal F, Crary F, Ebert RW, Elliott H, Stern A, Valek P. Diverse plasma populations and structures in Jupiter's magnetotail. Science 2007; 318:217-20. [PMID: 17932282 DOI: 10.1126/science.1147393] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [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
Jupiter's magnetotail is the largest cohesive structure in the solar system and marks the loss of vast numbers of heavy ions from the Jupiter system. The New Horizons spacecraft traversed the magnetotail to distances exceeding 2500 jovian radii (R(J)) and revealed a remarkable diversity of plasma populations and structures throughout its length. Ions evolve from a hot plasma disk distribution at approximately 100 R(J) to slower, persistent flows down the tail that become increasingly variable in flux and mean energy. The plasma is highly structured-exhibiting sharp breaks, smooth variations, and apparent plasmoids-and contains ions from both Io and Jupiter's ionosphere with intense bursts of H(+) and H(+)(3). Quasi-periodic changes were seen in flux at approximately 450 and approximately 1500 R(J) with a 10-hour period. Other variations in flow speed at approximately 600 to 1000 R(J) with a 3- to 4-day period may be attributable to plasmoids moving down the tail.
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Affiliation(s)
- D J McComas
- Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238, USA.
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28
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McNutt RL, Haggerty DK, Hill ME, Krimigis SM, Livi S, Ho GC, Gurnee RS, Mauk BH, Mitchell DG, Roelof EC, McComas DJ, Bagenal F, Elliott HA, Brown LE, Kusterer M, Vandegriff J, Stern SA, Weaver HA, Spencer JR, Moore JM. Energetic Particles in the Jovian Magnetotail. Science 2007; 318:220-2. [PMID: 17932283 DOI: 10.1126/science.1148025] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- R. L. McNutt
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - D. K. Haggerty
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - M. E. Hill
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - S. M. Krimigis
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - S. Livi
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - G. C. Ho
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - R. S. Gurnee
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - B. H. Mauk
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - D. G. Mitchell
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - E. C. Roelof
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - D. J. McComas
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - F. Bagenal
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - H. A. Elliott
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - L. E. Brown
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - M. Kusterer
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - J. Vandegriff
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - S. A. Stern
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - H. A. Weaver
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - J. R. Spencer
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
| | - J. M. Moore
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
- Academy of Athens, 28 Panapistimiou, 10679 Athens, Greece
- Southwest Research Institute, San Antonio, TX 78228, USA
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309–0392, USA
- NASA Headquarters, Washington, DC 20546–0001, USA
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Retherford KD, Spencer JR, Stern SA, Saur J, Strobel DF, Steffl AJ, Gladstone GR, Weaver HA, Cheng AF, Parker JW, Slater DC, Versteeg MH, Davis MW, Bagenal F, Throop HB, Lopes RMC, Reuter DC, Lunsford A, Conard SJ, Young LA, Moore JM. Io's Atmospheric Response to Eclipse: UV Aurorae Observations. Science 2007; 318:237-40. [DOI: 10.1126/science.1147594] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- K. D. Retherford
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - J. R. Spencer
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - S. A. Stern
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - J. Saur
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - D. F. Strobel
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - A. J. Steffl
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - G. R. Gladstone
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - H. A. Weaver
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - A. F. Cheng
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - J. Wm. Parker
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - D. C. Slater
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - M. H. Versteeg
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - M. W. Davis
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - F. Bagenal
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - H. B. Throop
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - R. M. C. Lopes
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - D. C. Reuter
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - A. Lunsford
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - S. J. Conard
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - L. A. Young
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
| | - J. M. Moore
- Southwest Research Institute, San Antonio, TX 78228, USA
- Southwest Research Institute, Boulder, CO 80302, USA
- NASA Headquarters, Washington, DC 20546, USA
- University of Cologne, 50923 Koln, Germany
- The Johns Hopkins University, Baltimore, MD 21218, USA
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Crary FJ, Bagenal F, Frank LA, Paterson WR. Galileo plasma spectrometer measurements of composition and temperature in the Io plasma torus. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/1998ja900003] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Russell CT, Bagenal F, Cheng AF, Ip WH, Roux A, Smyth WH, Bolton SJ, Polanskey CA. Io's interaction with the Jovian magnetosphere. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97eo00059] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bagenal F. Also Noteworthy: Physics of the Magnetopause. Science 1996. [DOI: 10.1126/science.272.5260.364a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Waite JH, Bagenal F, Seward F, Na C, Gladstone GR, Cravens TE, Hurley KC, Clarke JT, Elsner R, Stern SA. ROSAT observations of the Jupiter aurora. ACTA ACUST UNITED AC 1994. [DOI: 10.1029/94ja01005] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Belcher JW, Bridge HS, Bagenal F, Coppi B, Divers O, Eviatar A, Gordon GS, Lazarus AJ, McNutt RL, Ogilvie KW, Richardson JD, Siscoe GL, Sittler EC, Steinberg JT, Sullivan JD, Szabo A, Villanueva L, Vasyliunas VM, Zhang M. Plasma Observations Near Neptune: Initial Results from Voyager 2. Science 1989; 246:1478-83. [PMID: 17756003 DOI: 10.1126/science.246.4936.1478] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.
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Bridge HS, Belcher JW, Coppi B, Lazarus AJ, McNutt RL, Olbert S, Richardson JD, Sands MR, Selesnick RS, Sullivan JD, Hartle RE, Ogilvie KW, Sittler EC, Bagenal F, Wolff RS, Vasyliunas VM, Siscoe GL, Goertz CK, Eviatar A. Plasma Observations Near Uranus: Initial Results from Voyager 2. Science 1986; 233:89-93. [PMID: 17812895 DOI: 10.1126/science.233.4759.89] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Extensive measurements of low-energy positive ions and electrons in the vicinity of Uranus have revealed a fully developed magnetosphere. The magnetospheric plasma has a warm component with a temperature of 4 to 50 electron volts and a peak density of roughly 2 protons per cubic centimeter, and a hot component, with a temperature of a few kiloelectron volts and a peak density of roughly 0.1 proton per cubic centimeter. The warm component is observed both inside and outside of L = 5, whereas the hot component is excluded from the region inside of that L shell. Possible sources of the plasma in the magnetosphere are the extended hydrogen corona, the solar wind, and the ionosphere. The Uranian moons do not appear to be a significant plasma source. The boundary of the hot plasma component at L = 5 may be associated either with Miranda or with the inner limit of a deeply penetrating, solar wind-driven magnetospheric convection system. The Voyager 2 spacecraft repeatedly encountered the plasma sheet in the magnetotail at locations that are consistent with a geometric model for the plasma sheet similar to that at Earth.
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Bridge HS, Bagenal F, Belcher JW, Lazarus AJ, McNutt RL, Sullivan JD, Gazis PR, Hartle RE, Ogilvie KW, Scudder JD, Sittler EC, Eviatar A, Siscoe GL, Goertz CK, Vasyliunas VM. Plasma Observations Near Saturn: Initial Results from Voyager 2. Science 1982; 215:563-70. [PMID: 17771279 DOI: 10.1126/science.215.4532.563] [Citation(s) in RCA: 114] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Results of measurements of plasma electrons and poitive ions made during the Voyager 2 encounter with Saturn have been combined with measurements from Voyager 1 and Pioneer 11 to define more clearly the configuration of plasma in the Saturnian magnetosphere. The general morphology is well represented by four regions: (i) the shocked solar wind plasma in the magnetosheath, observed between about 30 and 22 Saturn radii (RS) near the noon meridian; (ii) a variable density region between approximately 17 RS and the magnetopause; (iii) an extended thick plasma sheet between approximately 17 and approximately 7 RS symmetrical with respect to Saturn's equatorial plane and rotation axis; and (iv) an inner plasma torus that probably originates from local sources and extends inward from L approximately 7 to less than L approximately 2.7 (L is the magnetic shell parameter). In general, the heavy ions, probably O(+), are more closely confined to the equatorial plane than H(+), so that the ratio of heavy to light ions varies along the trajectory according to the distance of the spacecraft from the equatorial plane. The general configuration of the plasma sheet at Saturn found by Voyager 1 is confirmed, with some notable differences and additions. The "extended plasma sheet," observed between L approximately 7 and L approximately 15 by Voyager 1 is considerably thicker as observed by Voyager 2. Inward of L approximately 4, the plasma sheet collapses to a thin region about the equatorial plane. At the ring plane crossing, L approximately 2.7, the observations are consistent with a density of O(+) of approximately 100 per cubic centimeter, with a temperature of approximately 10 electron volts. The location of the bow shock and magnetopause crossings were consistent with those previously observed. The entire magnetosphere was larger during the outbound passage of Voyager 2 than had been previously observed; however, a magnetosphere of this size or larger is expected approximately 3 percent of the time.
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Bridge HS, Belcher JW, Lazarus AJ, Olbert S, Sullivan JD, Bagenal F, Gazis PR, Hartle RE, Ogilvie KW, Scudder JD, Sittler EC, Eviatar A, Siscoe GL, Goertz CK, Vasyliunas VM. Plasma Observations Near Saturn: Initial Results from Voyager 1. Science 1981; 212:217-24. [PMID: 17783833 DOI: 10.1126/science.212.4491.217] [Citation(s) in RCA: 165] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Extensive measurements of low-energy plasma electrons and positive ions were made during the Voyager 1 encounter with Saturn and its satellites. The magnetospheric plasma contains light and heavy ions, probably hydrogen and nitrogen or oxygen; at radial distances between 15 and 7 Saturn-radii (Rs) on the inbound trajectory, the plasma appears to corotate with a velocity within 20 percent of that expected for rigid corotation. The general morphology of Saturn's magnetosphere is well represented by a plasma sheet that extends from at least 5 to 17 Rs, is symmetrical with respect to Saturn's equatorial plane and rotation axis, and appears to be well ordered by the magnetic shell parameter L (which represents the equatorial distance of a magnetic field line measured in units of Rs). Within this general configuration, two distinct structures can be identified: a central plasma sheet observed from L = 5 to L = 8 in which the density decreases rapidly away from the equatorial plane, and a more extended structure from L = 7 to beyond 18 Rs in which the density profile is nearly flat for a distance +/- 1.8 Rs off the plane and falls rapidly thereafter. The encounter with Titan took place inside the magnetosphere. The data show a clear signature characteristic of the interaction between a subsonic corotating magnetospheric plasma and the atmospheric or ionospheric exosphere of Titan. Titan appears to be a significant source of ions for the outer magnetosphere. The locations of bow shock crossings observed inbound and outbound indicate that the shape of the Saturnian magnetosphere is similar to that of Earth and that the position of the stagnation point scales approximately as the inverse one-sixth power of the ram pressure.
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Bridge HS, Belcher JW, Lazarus AJ, Sullivan JD, Bagenal F, McNutt RL, Ogilvie KW, Scudder JD, Sittler EC, Vasyliunas VM, Goertz CK. Plasma Observations Near Jupiter: Initial Results from Voyager 2. Science 1979; 206:972-6. [PMID: 17733917 DOI: 10.1126/science.206.4421.972] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The first of at least nine bow shock crossings observed on the inbound pass of Voyager 2 occurred at 98.8 Jupiter radii (R(J)) with final entry into the magnetosphere at 62 R(J). On both the inbound and outbound passes the plasma showed a tendency to move in the direction of corotation, as was observed on the inbound pass of Voyager 1. Positive ion densities and electron intensities observed by Voyager 2 are comparable within a factor of 2 to those seen by Voyager 1 at the same radial distance from Jupiter; the composition of the magnetospheric plasma is again dominated by heavy ions with a ratio of mass density relative to hydrogen of about 100/1. A series of dropouts of plasma intensity near Ganymede may be related to a complex interaction between Ganymede and the magnetospheric plasma. From the planetary spin modulation of the intensity of plasma electrons it is inferred that the plasma sheet is centered at the dipole magnetic equator out to a distance of 40 to 50 R(J) and deviates from it toward the rotational equator at larger distances. The longitudinal excursion of the plasma sheet lags behind the rotating dipole by a phase angle that increases with increasing radial distance.
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Bridge HS, Belcher JW, Lazarus AJ, Sullivan JD, McNutt RL, Bagenal F, Scudder JD, Sittler EC, Siscoe GL, Vasyliunas VM, Goertz CK, Yeates CM. Plasma Observations Near Jupiter: Initial Results from Voyager 1. Science 1979; 204:987-91. [PMID: 17800436 DOI: 10.1126/science.204.4396.987] [Citation(s) in RCA: 207] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Extensive measurements of low-energy positive ions and electrons were made throughout the Jupiter encounter of Voyager 1. The bow shock and magneto-pause were crossed several times at distances consistent with variations in the upstream solar wind pressure measured on Voyager 2. During the inbound pass, the number density increased by six orders of magnitude between the innermost magnetopause crossing at approximately 47 Jupiter radii and near closest approach at approximately 5 Jupiter radii; the plasma flow during this period was predominately in the direction of corotation. Marked increases in number density were observed twice per planetary rotation, near the magnetic equator. Jupiterward of the Io plasma torus, a cold, corotating plasma was observed and the energylcharge spectra show well-resolved, heavy-ion peaks at mass-to-charge ratios A/Z* = 8, 16, 32, and 64.
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