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Pilkington NM, Achilleos N, Arridge CS, Guio P, Masters A, Ray LC, Sergis N, Thomsen MF, Coates AJ, Dougherty MK. Internally driven large-scale changes in the size of Saturn's magnetosphere. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2015; 120:7289-7306. [PMID: 27867793 PMCID: PMC5111417 DOI: 10.1002/2015ja021290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 07/22/2015] [Accepted: 07/26/2015] [Indexed: 05/20/2023]
Abstract
Saturn's magnetic field acts as an obstacle to solar wind flow, deflecting plasma around the planet and forming a cavity known as the magnetosphere. The magnetopause defines the boundary between the planetary and solar dominated regimes, and so is strongly influenced by the variable nature of pressure sources both outside and within. Following from Pilkington et al. (2014), crossings of the magnetopause are identified using 7 years of magnetic field and particle data from the Cassini spacecraft and providing unprecedented spatial coverage of the magnetopause boundary. These observations reveal a dynamical interaction where, in addition to the external influence of the solar wind dynamic pressure, internal drivers, and hot plasma dynamics in particular can take almost complete control of the system's dayside shape and size, essentially defying the solar wind conditions. The magnetopause can move by up to 10-15 planetary radii at constant solar wind dynamic pressure, corresponding to relatively "plasma-loaded" or "plasma-depleted" states, defined in terms of the internal suprathermal plasma pressure.
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Affiliation(s)
- N. M. Pilkington
- Atmospheric Physics Laboratory, Department of Physics and AstronomyUniversity College LondonLondonUK
- The Centre for Planetary SciencesUCL/BirkbeckLondonUK
| | - N. Achilleos
- Atmospheric Physics Laboratory, Department of Physics and AstronomyUniversity College LondonLondonUK
- The Centre for Planetary SciencesUCL/BirkbeckLondonUK
| | | | - P. Guio
- Atmospheric Physics Laboratory, Department of Physics and AstronomyUniversity College LondonLondonUK
- The Centre for Planetary SciencesUCL/BirkbeckLondonUK
| | - A. Masters
- Blackett LaboratoryImperial College LondonLondonUK
| | - L. C. Ray
- Atmospheric Physics Laboratory, Department of Physics and AstronomyUniversity College LondonLondonUK
- The Centre for Planetary SciencesUCL/BirkbeckLondonUK
| | - N. Sergis
- Academy of AthensOffice of Space Research and TechnologyAthensGreece
| | | | - A. J. Coates
- The Centre for Planetary SciencesUCL/BirkbeckLondonUK
- Mullard Space Science Laboratory, Department of Space and Climate PhysicsUniversity College LondonDorkingUK
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Heller R, Williams D, Kipping D, Limbach MA, Turner E, Greenberg R, Sasaki T, Bolmont É, Grasset O, Lewis K, Barnes R, Zuluaga JI. Formation, habitability, and detection of extrasolar moons. ASTROBIOLOGY 2014; 14:798-835. [PMID: 25147963 PMCID: PMC4172466 DOI: 10.1089/ast.2014.1147] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 06/05/2014] [Indexed: 06/03/2023]
Abstract
The diversity and quantity of moons in the Solar System suggest a manifold population of natural satellites exist around extrasolar planets. Of peculiar interest from an astrobiological perspective, the number of sizable moons in the stellar habitable zones may outnumber planets in these circumstellar regions. With technological and theoretical methods now allowing for the detection of sub-Earth-sized extrasolar planets, the first detection of an extrasolar moon appears feasible. In this review, we summarize formation channels of massive exomoons that are potentially detectable with current or near-future instruments. We discuss the orbital effects that govern exomoon evolution, we present a framework to characterize an exomoon's stellar plus planetary illumination as well as its tidal heating, and we address the techniques that have been proposed to search for exomoons. Most notably, we show that natural satellites in the range of 0.1-0.5 Earth mass (i) are potentially habitable, (ii) can form within the circumplanetary debris and gas disk or via capture from a binary, and (iii) are detectable with current technology.
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Affiliation(s)
- René Heller
- Origins Institute, Department of Physics and Astronomy, McMaster University, Hamilton, Canada
| | - Darren Williams
- The Behrend College School of Science, Penn State Erie, Erie, Pennsylvania, USA
| | - David Kipping
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
| | - Mary Anne Limbach
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey, USA
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey, USA
| | - Edwin Turner
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey, USA
- The Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, Kashiwa, Japan
| | - Richard Greenberg
- Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona, USA
| | | | - Émeline Bolmont
- Université de Bordeaux, LAB, UMR 5804, Floirac, France
- CNRS, LAB, UMR 5804, Floirac, France
| | - Olivier Grasset
- Planetology and Geodynamics, University of Nantes, CNRS, Nantes, France
| | - Karen Lewis
- Earth and Planetary Sciences, Tokyo Institute of Technology, Tokyo, Japan
| | - Rory Barnes
- Astronomy Department, University of Washington, Seattle, Washington, USA
- NASA Astrobiology Institute—Virtual Planetary Laboratory Lead Team, USA
| | - Jorge I. Zuluaga
- FACom—Instituto de Física—FCEN, Universidad de Antioquia, Medellín, Colombia
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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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Jia X, Hansen KC, Gombosi TI, Kivelson MG, Tóth G, DeZeeuw DL, Ridley AJ. Magnetospheric configuration and dynamics of Saturn's magnetosphere: A global MHD simulation. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012ja017575] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Nichols JD. Magnetosphere-ionosphere coupling in Jupiter's middle magnetosphere: Computations including a self-consistent current sheet magnetic field model. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011ja016922] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- J. D. Nichols
- Department of Physics and Astronomy; University of Leicester; Leicester UK
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Went DR, Hospodarsky GB, Masters A, Hansen KC, Dougherty MK. A new semiempirical model of Saturn's bow shock based on propagated solar wind parameters. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010ja016349] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- D. R. Went
- Blackett Laboratory; Imperial College London; London UK
| | - G. B. Hospodarsky
- Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
| | - A. Masters
- Centre for Planetary Sciences; University College London/Birkbeck; London UK
- Mullard Space Science Laboratory, Department of Space and Climate Physics; University College London; Dorking UK
| | - K. C. Hansen
- Space Research Building; University of Michigan; Ann Arbor Michigan USA
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Bagenal F, Delamere PA. Flow of mass and energy in the magnetospheres of Jupiter and Saturn. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010ja016294] [Citation(s) in RCA: 222] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Fran Bagenal
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | - Peter A. Delamere
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
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Kanani SJ, Arridge CS, Jones GH, Fazakerley AN, McAndrews HJ, Sergis N, Krimigis SM, Dougherty MK, Coates AJ, Young DT, Hansen KC, Krupp N. A new form of Saturn's magnetopause using a dynamic pressure balance model, based on in situ, multi-instrument Cassini measurements. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009ja014262] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- S. J. Kanani
- Mullard Space Science Laboratory; University College London; London UK
| | - C. S. Arridge
- Mullard Space Science Laboratory; University College London; London UK
| | - G. H. Jones
- Mullard Space Science Laboratory; University College London; London UK
| | - A. N. Fazakerley
- Mullard Space Science Laboratory; University College London; London UK
| | | | | | - S. M. Krimigis
- Applied Physics Laboratory; Johns Hopkins University; Baltimore Maryland USA
| | | | - A. J. Coates
- Mullard Space Science Laboratory; University College London; London UK
| | - D. T. Young
- Southwest Research Institute; San Antonio Texas USA
| | | | - N. Krupp
- Max-Planck-Institut für Sonnensystemforschung; Katlenberg-Lindau Germany
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Achilleos N, Arridge CS, Bertucci C, Jackman CM, Dougherty MK, Khurana KK, Russell CT. Large-scale dynamics of Saturn's magnetopause: Observations by Cassini. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008ja013265] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- N. Achilleos
- Atmospheric Physics Laboratory, Center for Planetary Sciences; University College London; London UK
- Blackett Laboratory; Imperial College London; London UK
| | - C. S. Arridge
- Blackett Laboratory; Imperial College London; London UK
- Mullard Space Science Laboratory, Center for Planetary Sciences; University College London, Holmbury St Mary; London UK
| | - C. Bertucci
- Blackett Laboratory; Imperial College London; London UK
| | - C. M. Jackman
- Blackett Laboratory; Imperial College London; London UK
| | | | - K. K. Khurana
- Institute of Geophysics and Planetary Physics; University of California-Los Angeles; Los Angeles California USA
| | - C. T. Russell
- Institute of Geophysics and Planetary Physics; University of California-Los Angeles; Los Angeles California USA
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Masters A, Achilleos N, Dougherty MK, Slavin JA, Hospodarsky GB, Arridge CS, Coates AJ. An empirical model of Saturn's bow shock: Cassini observations of shock location and shape. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008ja013276] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. Masters
- Space and Atmospheric Physics Group, The Blackett Laboratory; Imperial College London; London UK
| | - N. Achilleos
- Atmospheric Physics Laboratory, Department of Physics and Astronomy; University College London; London UK
| | - M. K. Dougherty
- Space and Atmospheric Physics Group, The Blackett Laboratory; Imperial College London; London UK
| | - J. A. Slavin
- Heliophysics Science Division; NASA GSFC; Greenbelt Maryland USA
| | - G. B. Hospodarsky
- Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
| | - C. S. Arridge
- Mullard Space Science Laboratory, Department of Space and Climate Physics; University College London; Dorking UK
- Centre for Planetary Sciences; University College London; London UK
| | - A. J. Coates
- Mullard Space Science Laboratory, Department of Space and Climate Physics; University College London; Dorking UK
- Centre for Planetary Sciences; University College London; London UK
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Bunce EJ, Cowley SWH, Alexeev II, Arridge CS, Dougherty MK, Nichols JD, Russell CT. Cassini observations of the variation of Saturn's ring current parameters with system size. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2007ja012275] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- E. J. Bunce
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - S. W. H. Cowley
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - I. I. Alexeev
- Skobeltsyn Institute of Nuclear Physics; Lomonosov Moscow State University; Moscow Russia
| | - C. S. Arridge
- Mullard Space Science Laboratory; University College London; Dorking UK
| | - M. K. Dougherty
- Space and Atmospheric Physics, Blackett Laboratory; Imperial College; London UK
| | - J. D. Nichols
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - C. T. Russell
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
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Nichols JD, Bunce EJ, Clarke JT, Cowley SWH, Gérard JC, Grodent D, Pryor WR. Response of Jupiter's UV auroras to interplanetary conditions as observed by the Hubble Space Telescope during the Cassini flyby campaign. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006ja012005] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- J. D. Nichols
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - E. J. Bunce
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - J. T. Clarke
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - S. W. H. Cowley
- Department of Physics and Astronomy; University of Leicester; Leicester UK
| | - J.-C. Gérard
- LPAP, Institut d'Astrophysique et de Géophysique; Université de Liège; Liège Belgium
| | - D. Grodent
- LPAP, Institut d'Astrophysique et de Géophysique; Université de Liège; Liège Belgium
| | - W. R. Pryor
- Central Arizona College; Coolidge Arizona USA
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Joy SP, Kivelson MG, Walker RJ, Khurana KK, Russell CT, Paterson WR. Mirror mode structures in the Jovian magnetosheath. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006ja011985] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Arridge CS, Achilleos N, Dougherty MK, Khurana KK, Russell CT. Modeling the size and shape of Saturn's magnetopause with variable dynamic pressure. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005ja011574] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kronberg EA. Mass release at Jupiter: Substorm-like processes in the Jovian magnetotail. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004ja010777] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Hanlon PG. Dual spacecraft observations of a compression event within the Jovian magnetosphere: Signatures of externally triggered supercorotation? ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003ja010116] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Szego K. Cassini plasma spectrometer measurements of Jovian bow shock structure. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002ja009517] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Joy SP. Probabilistic models of the Jovian magnetopause and bow shock locations. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001ja009146] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Southwood DJ, Kivelson MG. A new perspective concerning the influence of the solar wind on the Jovian magnetosphere. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000ja000236] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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