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Cochrane CJ, Vance SD, Nordheim TA, Styczinski MJ, Masters A, Regoli LH. In Search of Subsurface Oceans Within the Uranian Moons. J Geophys Res Planets 2021; 126:e2021JE006956. [PMID: 35859709 PMCID: PMC9285391 DOI: 10.1029/2021je006956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 11/03/2021] [Accepted: 11/11/2021] [Indexed: 05/04/2023]
Abstract
The Galileo mission to Jupiter discovered magnetic signatures associated with hidden subsurface oceans at the moons Europa and Callisto using the phenomenon of magnetic induction. These induced magnetic fields originate from electrically conductive layers within the moons and are driven by Jupiter's strong time-varying magnetic field. The ice giants and their moons are also ideal laboratories for magnetic induction studies. Both Uranus and Neptune have a strongly tilted magnetic axis with respect to their spin axis, creating a dynamic and strongly variable magnetic field environment at the orbits of their major moons. Although Voyager 2 visited the ice giants in the 1980s, it did not pass close enough to any of the moons to detect magnetic induction signatures. However, Voyager 2 revealed that some of these moons exhibit surface features that hint at recent geologically activity, possibly associated with subsurface oceans. Future missions to the ice giants may therefore be capable of discovering subsurface oceans, thereby adding to the family of known "ocean worlds" in our Solar System. Here, we assess magnetic induction as a technique for investigating subsurface oceans within the major moons of Uranus. Furthermore, we establish the ability to distinguish induction responses created by different interior characteristics that tie into the induction response: ocean thickness, conductivity and depth, and ionospheric conductance. The results reported here demonstrate the possibility of single-pass ocean detection and constrained characterization within the moons of Miranda, Ariel, and Umbriel, and provide guidance for magnetometer selection and trajectory design for future missions to Uranus.
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Affiliation(s)
- C. J. Cochrane
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - S. D. Vance
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - T. A. Nordheim
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | | | - L. H. Regoli
- Applied Physics LaboratoryJohn Hopkins UniversityBaltimoreMDUSA
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Cochrane CJ, Vance SD, Nordheim TA, Styczinski MJ, Masters A, Regoli LH. In Search of Subsurface Oceans Within the Uranian Moons. J Geophys Res Planets 2021. [PMID: 35859709 DOI: 10.1029/2020je006418] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The Galileo mission to Jupiter discovered magnetic signatures associated with hidden subsurface oceans at the moons Europa and Callisto using the phenomenon of magnetic induction. These induced magnetic fields originate from electrically conductive layers within the moons and are driven by Jupiter's strong time-varying magnetic field. The ice giants and their moons are also ideal laboratories for magnetic induction studies. Both Uranus and Neptune have a strongly tilted magnetic axis with respect to their spin axis, creating a dynamic and strongly variable magnetic field environment at the orbits of their major moons. Although Voyager 2 visited the ice giants in the 1980s, it did not pass close enough to any of the moons to detect magnetic induction signatures. However, Voyager 2 revealed that some of these moons exhibit surface features that hint at recent geologically activity, possibly associated with subsurface oceans. Future missions to the ice giants may therefore be capable of discovering subsurface oceans, thereby adding to the family of known "ocean worlds" in our Solar System. Here, we assess magnetic induction as a technique for investigating subsurface oceans within the major moons of Uranus. Furthermore, we establish the ability to distinguish induction responses created by different interior characteristics that tie into the induction response: ocean thickness, conductivity and depth, and ionospheric conductance. The results reported here demonstrate the possibility of single-pass ocean detection and constrained characterization within the moons of Miranda, Ariel, and Umbriel, and provide guidance for magnetometer selection and trajectory design for future missions to Uranus.
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Affiliation(s)
- C J Cochrane
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - S D Vance
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | - T A Nordheim
- Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
| | | | | | - L H Regoli
- Applied Physics Laboratory John Hopkins University Baltimore MD USA
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Turrini D, Codella C, Danielski C, Fedele D, Fonte S, Garufi A, Guarcello MG, Helled R, Ikoma M, Kama M, Kimura T, Kruijssen JMD, Maldonado J, Miguel Y, Molinari S, Nikolaou A, Oliva F, Panić O, Pignatari M, Podio L, Rickman H, Schisano E, Shibata S, Vazan A, Wolkenberg P. Exploring the link between star and planet formation with Ariel. Exp Astron (Dordr) 2021; 53:225-278. [PMID: 35673554 PMCID: PMC9166885 DOI: 10.1007/s10686-021-09754-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 04/13/2021] [Indexed: 06/13/2023]
Abstract
The goal of the Ariel space mission is to observe a large and diversified population of transiting planets around a range of host star types to collect information on their atmospheric composition. The planetary bulk and atmospheric compositions bear the marks of the way the planets formed: Ariel's observations will therefore provide an unprecedented wealth of data to advance our understanding of planet formation in our Galaxy. A number of environmental and evolutionary factors, however, can affect the final atmospheric composition. Here we provide a concise overview of which factors and effects of the star and planet formation processes can shape the atmospheric compositions that will be observed by Ariel, and highlight how Ariel's characteristics make this mission optimally suited to address this very complex problem.
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Affiliation(s)
- Diego Turrini
- Institute of Space Astrophysics and Planetology INAF-IAPS, Via Fosso del Cavaliere 100, I-00133 Rome, Italy
- INAF - Osservatorio Astrofisico di Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy
| | - Claudio Codella
- INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50127 Firenze, Italy
| | - Camilla Danielski
- Instituto de Astrofísica de Andalucía (IAA-CSIC), Glorieta de la Astronomía s/n, 18008 Granada, Spain
| | - Davide Fedele
- INAF - Osservatorio Astrofisico di Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy
- INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50127 Firenze, Italy
| | - Sergio Fonte
- Institute of Space Astrophysics and Planetology INAF-IAPS, Via Fosso del Cavaliere 100, I-00133 Rome, Italy
| | - Antonio Garufi
- INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50127 Firenze, Italy
| | | | - Ravit Helled
- Institute for Computational Science, Center for Theoretical Astrophysics and Cosmology, University of Zurich, CH-8057 Zurich, Switzerland
| | - Masahiro Ikoma
- Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan
| | - Mihkel Kama
- Department of Physics and Astronomy, University College London, London, WC1E 6BT UK
- Tartu Observatory, University of Tartu, Observatooriumi 1, 61602 Tõravere, Estonia
| | - Tadahiro Kimura
- Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan
| | - J. M. Diederik Kruijssen
- Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstraße 12-14, 69120 Heidelberg, Germany
| | - Jesus Maldonado
- INAF - Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, I-90134 Palermo, Italy
| | - Yamila Miguel
- Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
- SRON - Netherlands Institute for Space Research, Sorbonnelaan 2, NL-3584 CA Utrecht, The Netherlands
| | - Sergio Molinari
- Institute of Space Astrophysics and Planetology INAF-IAPS, Via Fosso del Cavaliere 100, I-00133 Rome, Italy
| | - Athanasia Nikolaou
- Sapienza University of Rome, Piazzale Aldo Moro 2, Rome, 00185 Italy
- European Space Agency, ESRIN, ESA Φ-lab, Largo Galileo Galilei 1, 00044 Frascati, Italy
| | - Fabrizio Oliva
- Institute of Space Astrophysics and Planetology INAF-IAPS, Via Fosso del Cavaliere 100, I-00133 Rome, Italy
| | - Olja Panić
- School of Physics and Astronomy, E. C. Stoner Building, University of Leeds, Leeds, LS2 9JT UK
| | - Marco Pignatari
- E.A. Milne Centre for Astrophysics, Department of Physics, Mathematics, University of Hull, Hull, HU6 7RX UK
- Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklos ut 15-17, H-1121 Budapest, Hungary
- Joint Institute for Nuclear Astrophysics - Center for the Evolution of the Elements & NuGrid Collaboration, www.nugridstars.org, Notre Dame, USA
| | - Linda Podio
- INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50127 Firenze, Italy
| | - Hans Rickman
- Centrum Badań Kosmicznykh Polskiej Akademii Nauk (CBK PAN), Bartycka 18A, 00-716 Warszawa, Poland
| | - Eugenio Schisano
- Institute of Space Astrophysics and Planetology INAF-IAPS, Via Fosso del Cavaliere 100, I-00133 Rome, Italy
| | - Sho Shibata
- Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan
| | - Allona Vazan
- Department of Natural Sciences and Astrophysics Research Center of the Open university (ARCO), The Open University of Israel, 4353701 Raanana, Israel
| | - Paulina Wolkenberg
- Institute of Space Astrophysics and Planetology INAF-IAPS, Via Fosso del Cavaliere 100, I-00133 Rome, Italy
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König C, Honecker B, Wilson IW, Weedall GD, Hall N, Roeder T, Metwally NG, Bruchhaus I. Taxon-Specific Proteins of the Pathogenic Entamoeba Species E. histolytica and E. nuttalli. Front Cell Infect Microbiol 2021; 11:641472. [PMID: 33816346 PMCID: PMC8017271 DOI: 10.3389/fcimb.2021.641472] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/03/2021] [Indexed: 01/30/2023] Open
Abstract
The human protozoan parasite Entamoeba histolytica can live in the human intestine for months or years without generating any symptoms in the host. For unknown reasons, amoebae can suddenly destroy the intestinal mucosa and become invasive. This can lead to amoebic colitis or extraintestinal amoebiasis whereby the amoebae spread to other organs via the blood vessels, most commonly the liver where abscesses develop. Entamoeba nuttalli is the closest genetic relative of E. histolytica and is found in wild macaques. Another close relative is E. dispar, which asyptomatically infects the human intestine. Although all three species are closely related, only E. histolytica and E. nuttalli are able to penetrate their host’s intestinal epithelium. Lineage-specific genes and gene families may hold the key to understanding differences in virulence among species. Here we discuss those genes found in E. histolytica that have relatives in only one or neither of its sister species, with particular focus on the peptidase, AIG, Ariel, and BspA families.
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Affiliation(s)
- Constantin König
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Barbara Honecker
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Ian W Wilson
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Gareth D Weedall
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Neil Hall
- Earlham Institute, Norwich, United Kingdom.,School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Thomas Roeder
- Zoology, Department of Molecular Physiology, Kiel University, Kiel, Germany.,Airway Research Center North (ARCN), German Center for Lung Research (DZL), Kiel, Germany
| | | | - Iris Bruchhaus
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.,Department of Biology, University of Hamburg, Hamburg, Germany
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