Mysterious High Energy Gamma Rays Might Help Explain What Drives Solar Cycles
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Effects of the Interplanetary Magnetic Field Y Component on the Dayside
Liou and Mitchell Geosci. Lett. (2019) 6:11 https://doi.org/10.1186/s40562-019-0141-3 RESEARCH LETTER Open Access Efects of the interplanetary magnetic feld y component on the dayside aurora K. Liou* and E. Mitchell Abstract A dawn–dusk asymmetry in many high-latitude ionospheric and magnetospheric phenomena, including the aurora, can be linked to the east–west (y) component of the interplanetary magnetic feld (IMF). Owing to the scarcity of observations in the Southern Hemisphere, most of the previous fndings are associated with the Northern Hemi- sphere. It has long been suspected that if the IMF By component also produces a dawn–dusk asymmetry and/or a mirror image in the Southern Hemisphere as predicted by some theories. The present study explores the efect of the IMF By component on the dayside aurora from both hemispheres by analyzing the auroral emission data from the Global UltraViolet scanning spectrograph Imager on board the Thermosphere Ionosphere Mesosphere Energetics and Dynamics mission spacecraft from 2002 to 2007. The data set comprises 28,774 partial images of the northern hemispheric oval and 29,742 partial images of the southern hemispheric oval, allowing for a statistical analysis. It is found that even though auroras in diferent regions of the dayside oval respond diferently to the orientation of the IMF By component, their responses are opposite between the two hemispheres. For example, at ~ 1400–1600 MLT in the Northern Hemisphere, where the so-called 1500 MLT auroral hot spots occur, peak auroral energy fux is larger for negative IMF By comparing to positive IMF By. -
Small-Scale Flux Transfer Events Formed in the Reconnection Exhaust Region Between Two X Lines
Journal of Geophysical Research: Space Physics RESEARCH ARTICLE Small-Scale Flux Transfer Events Formed in the Reconnection 10.1029/2018JA025611 Exhaust Region Between Two X Lines Key Points: K.-J. Hwang1 , D. G. Sibeck2 , J. L. Burch1 , E. Choi1 , R. C. Fear3 , B. Lavraud4 , • fl MMS observation of ion-scale ux 2 2 5 6 7 ropes in the reconnection outflow B. L. Giles , D. Gershman , C. J. Pollock , J. P. Eastwood , Y. Khotyaintsev , 8 9 10 11 12 region Philippe Escoubet ,H.Fu , S. Toledo-Redondo , R. B. Torbert , R. E. Ergun , • The initial X line is embedded in the W. R. Paterson2 , J. C. Dorelli2 , L. Avanov2,13 , C. T. Russell14 , and R. J. Strangeway14 exhaust region downstream of a second X line 1Southwest Research Institute, San Antonio, TX, USA, 2NASA Goddard Space Flight Center, Greenbelt, MD, USA, 3Physics • Flux transfer events (FTE) are formed 4 between the two X lines due to and Astronomy, University of Southampton, Southampton, UK, Institut de Recherche en Astrophysique et Planétologie, 5 6 tearing instability CNRS, UPS, CNES, Université de Toulouse, Toulouse, France, Denali Scientific, LLC, Fairbanks, AK, USA, Imperial College, London, UK, 7Swedish Institute of Space Physics, Uppsala, Sweden, 8European Space Agency, Noordwijk, Netherlands, 9School of Space and Environment, Beihang University, Beijing, China, 10European Space Agency, ESAC, Madrid, Spain, 11Space Science Center, University of New Hampshire, Durham, NH, USA, 12Laboratory for Atmospheric and Space Physics, Correspondence to: University of Colorado Boulder, Boulder, CO, USA, 13The Goddard Planetary Heliophysics Institute, Baltimore, MD, USA, K.-J. Hwang, 14 [email protected] Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, USA Citation: Abstract We report MMS observations of the ion-scale flux transfer events (FTEs) that may involve two Hwang, K.-J., Sibeck, D. -
The UV Aurora and Ionospheric Flows During Flux Transfer Events D
The UV aurora and ionospheric flows during flux transfer events D. A. Neudegg, S. W. H. Cowley, K. A. Mcwilliams, M. Lester, T. K. Yeoman, J. B. Sigwarth, G. Haerendel, W. Baumjohann, U. Auster, G.-H. Fornacon, et al. To cite this version: D. A. Neudegg, S. W. H. Cowley, K. A. Mcwilliams, M. Lester, T. K. Yeoman, et al.. The UV aurora and ionospheric flows during flux transfer events. Annales Geophysicae, European Geosciences Union, 2001, 19 (2), pp.179-188. hal-00316762 HAL Id: hal-00316762 https://hal.archives-ouvertes.fr/hal-00316762 Submitted on 1 Jan 2001 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. c Annales Geophysicae (2001) 19: 179–188 European Geophysical Society 2001 Annales Geophysicae The UV aurora and ionospheric flows during flux transfer events D. A. Neudegg1,*, S. W. H. Cowley1, K. A. McWilliams1, M. Lester1, T. K. Yeoman1, J. Sigwarth2, G. Haerendel3, W. Baumjohann3, U. Auster4, K.-H. Fornacon4, and E. Georgescu5 1Department of Physics and Astronomy, Leicester University, Leicester LE1 7RH, UK 2Department of Physics, University of Iowa, USA 3Max-Planck Institut für Extraterrestrische Physik, Garching, Germany 4Technische Universität von Braunschweig, Braunschweig, Germany 5Institute of Space Science, Bucharest, Romania *Now at: Rutherford-Appleton Laboratory, Oxfordshire OX11 0QX, UK Received: 24 July 2000 – Revised: 11 December 2000 – Accepted: 12 December 2000 Abstract. -
Recent Progress in Physics-Based Models of the Plasmasphere
Space Sci Rev (2009) 145: 193–229 DOI 10.1007/s11214-008-9480-7 Recent Progress in Physics-Based Models of the Plasmasphere Viviane Pierrard · Jerry Goldstein · Nicolas André · Vania K. Jordanova · Galina A. Kotova · Joseph F. Lemaire · Mike W. Liemohn · Hiroshi Matsui Received: 9 July 2008 / Accepted: 5 December 2008 / Published online: 23 January 2009 © Springer Science+Business Media B.V. 2009 V. Pierrard () · J.F. Lemaire Belgian Institute for Space Aeronomy (IASB-BIRA), 3 Avenue Circulaire, 1180 Brussels, Belgium e-mail: [email protected] J.F. Lemaire e-mail: [email protected] V. Pierrard · J.F. Lemaire Center for Space Radiations (CSR), Louvain-La-Neuve, Belgium J. Goldstein Space Science and Engineering Division, Southwest Research Institute (SwRI), San Antonio, TX, USA e-mail: [email protected] N. André Research and Scientific Support Department (RSSD), ESTEC/ESA, Noordwijk, The Netherlands e-mail: [email protected] V.K. Jordanova Space Science and Applications, Los Alamos National Laboratory (LANL), Los Alamos, NM, USA e-mail: [email protected] G.A. Kotova Space Research Institute (RSSI), Russian Academy of Science, Moscow, Russia e-mail: [email protected] M.W. Liemohn Atmospheric, Oceanic, and Space Sciences Department, University of Michigan, Ann Arbor, MI, USA e-mail: [email protected] H. Matsui University of New Hampshire (UNH), Space Science Center Morse Hall, Durham, NH, USA e-mail: [email protected] 194 V. Pierrard et al. Abstract We describe recent progress in physics-based models of the plasmasphere using the fluid and the kinetic approaches. Global modeling of the dynamics and influence of the plasmasphere is presented. -
Motion of Flux Transfer Events: a Test of the Cooling Model R
Motion of flux transfer events: a test of the Cooling model R. C. Fear, S. E. Milan, A. N. Fazakerley, C. J. Owen, T. Asikainen, M. G. G. T. Taylor, E. A. Lucek, H. Rème, I. Dandouras, P. W. Daly To cite this version: R. C. Fear, S. E. Milan, A. N. Fazakerley, C. J. Owen, T. Asikainen, et al.. Motion of flux transfer events: a test of the Cooling model. Annales Geophysicae, European Geosciences Union, 2007, 25 (7), pp.1669-1690. hal-00330141 HAL Id: hal-00330141 https://hal.archives-ouvertes.fr/hal-00330141 Submitted on 30 Jul 2007 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Ann. Geophys., 25, 1669–1690, 2007 www.ann-geophys.net/25/1669/2007/ Annales © European Geosciences Union 2007 Geophysicae Motion of flux transfer events: a test of the Cooling model R. C. Fear1, S. E. Milan1, A. N. Fazakerley2, C. J. Owen2, T. Asikainen3, M. G. G. T. Taylor4, E. A. Lucek5, H. Reme` 6, I. Dandouras6, and P. W. Daly7 1Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH, UK 2Mullard Space Science Laboratory, University College London, Holmbury St. -
Flux Transfer Events: 1
Annales Geophysicae, 24, 381–392, 2006 SRef-ID: 1432-0576/ag/2006-24-381 Annales © European Geosciences Union 2006 Geophysicae Flux Transfer Events: 1. generation mechanism for strong southward IMF J. Raeder Space Science Center, University of New Hampshire, Durham, NH 03824, USA Received: 30 December 2004 – Revised: 22 November 2005 – Accepted: 3 January 2006 – Published: 7 March 2006 Abstract. We use a global numerical model of the interac- ionosphere-atmosphere system. Reconnection opens up the tion of the solar wind and the interplanetary magnetic field magnetosphere so that magnetic field lines of the magneto- with Earth’s magnetosphere to study the formation process of sphere can directly connect to the IMF. Without reconnection Flux Transfer Events (FTEs) during strong southward IMF. the magnetosphere would be closed and there would be very We find that: (i) The model produces essentially all obser- little influence from the solar wind (SW) and IMF on the vational features expected for FTEs, in particular the bipolar magnetosphere. signature of the magnetic field BN component, the correct Although the reconnection between the Earth’s magnetic polarity, duration, and intermittency of that bipolar signa- field and the IMF was in dispute at the beginning of magne- ture, strong core fields and enhanced core pressure, and flow tospheric research (Axford and Hines, 1961) it is now well enhancements; (ii) FTEs only develop for large dipole tilt established that reconnection occurs at the day side magne- whereas in the case of no dipole tilt steady magnetic recon- topause. (Haerendel et al., 1978; Paschmann et al., 1979; nection occurs at the dayside magnetopause; (iii) the basic Cowley, 1980, 1982). -
General Disclaimer One Or More of the Following Statements May Affect
General Disclaimer One or more of the Following Statements may affect this Document This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible. This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available. This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white. This document is paginated as submitted by the original source. Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission. Produced by the NASA Center for Aerospace Information (CASI) NASA Technical Memorandum 84949 A NEW THEORY OF SOURCES OF BI RKELAN D CURRENTS K. D. Cale (NASA-TH-84949) A NEW THEORY OF SOURCES OF h83-15128 BIRKELAND CURRENTS (NASA) 48 p HC A0.3/HF A01 CSCL 20I Unclas G3/75 01780 ki SEPTEMBER 1982 4^ 'e National Aeronautics and .L .^ 1 l Space Administration Goddard Space Flight Center Greenbelt, Maryland 20771 .. .. +t ^lta IA11119VN'AF^N9^IIIrM ^'!lM^II^YNM^IIMI4111 pa1t1 F i A NEW THEORY OF SOUXES OF BIRKELAND CURRENTS t^ by K. D. Cole NASA/Goddard Space Flight Center Laboratory for Planetary Atmospheres Greenbelt, MD 20771 { ti September. 1982 (i) f^ 0 ORIGINAL PAGE POOR QU A New Theory of sources of Birkeland Currents by K. -
Visualizing Space Weather: Acquiring and Rendering Data of Earth's Magnetosphere Hans-Christian Helltegen
LiU-ITN-TEK-A14/052 SE Visualizing Space Weather: Acquiring and Rendering Data of Earth's Magnetosphere Hans-Christian Helltegen 2014-12-18 Department of Science and Technology Institutionen för teknik och naturvetenskap Linköping University Linköpings universitet nedewS ,gnipökrroN 47 106-ES 47 ,gnipökrroN nedewS 106 47 gnipökrroN LiU-ITN-TEK-A14/052 SE Visualizing Space Weather: Acquiring and Rendering Data of Earth's Magnetosphere Examensarbete utfört i Datateknik vid Tekniska högskolan vid Linköpings universitet Hans-Christian Helltegen Handledare Alexander Bock Examinator Anders Ynnerman Norrköping 2014-12-18 Upphovsrätt Detta dokument hålls tillgängligt på Internet – eller dess framtida ersättare – under en längre tid från publiceringsdatum under förutsättning att inga extra- ordinära omständigheter uppstår. Tillgång till dokumentet innebär tillstånd för var och en att läsa, ladda ner, skriva ut enstaka kopior för enskilt bruk och att använda det oförändrat för ickekommersiell forskning och för undervisning. Överföring av upphovsrätten vid en senare tidpunkt kan inte upphäva detta tillstånd. All annan användning av dokumentet kräver upphovsmannens medgivande. För att garantera äktheten, säkerheten och tillgängligheten finns det lösningar av teknisk och administrativ art. Upphovsmannens ideella rätt innefattar rätt att bli nämnd som upphovsman i den omfattning som god sed kräver vid användning av dokumentet på ovan beskrivna sätt samt skydd mot att dokumentet ändras eller presenteras i sådan form eller i sådant sammanhang som är kränkande för upphovsmannens litterära eller konstnärliga anseende eller egenart. För ytterligare information om Linköping University Electronic Press se förlagets hemsida http://www.ep.liu.se/ Copyright The publishers will keep this document online on the Internet - or its possible replacement - for a considerable time from the date of publication barring exceptional circumstances. -
Kristian Birkeland: the Great Norwegian Scientist That Nobody Knows
KRISTIAN BIRKELAND: THE GREAT NORWEGIAN SCIENTIST THAT NOBODY KNOWS Birkelandforelesningen 15. Juni 2017 av professor David Southwood, Imperial College, London Introduction Ask a foreigner for the name of a famous Norwegian. Rapidly one discovers that the late nineteenth century produced a flowering of Norwegian cultural talent as, as likely as not, the nominee will come from that time. These were, of course, years of an increasing sense of Norwegian identity, the years lead - ing up to Norway’s independence from Sweden in 1905. The list of Norwe - gians easily identified by a foreigner would surely include Henrik Ibsen, Edvard Munch, Edvard Grieg, Fridtjof Nansen, Roald Amundsen. However, one man would be missing. Despite being featured on the tail planes of Nor - wegian airliners and familiar to Norwegians after featuring for 20 years on the 200 NoK banknote, Kristian Birkeland will not leap to foreigners’ minds. Even if you asked for a scientist, one might get Abel, Lie or Bjerknes before Birkeland. Why is that so? Here I shall attempt to explain this conundrum. A detailed biography has been given by Egeland and Burke (2005). In ad - dition, an English journalist (Jago, 2001), has written a biography that is al - most a novelisation of his life. That this could be done, marks how multifaceted this man was. Birkeland was obsessed with the Northern Lights. The elegant picture in Figure 1 illustrates this, and Jago brings out this clearly. Egeland and Burke, both scientists, make clear how close he came to understanding their origin. I’ll try not to repeat too much of what is told in the two books. -
MESSENGER Observations of Large Dayside Flux Transfer Events
PUBLICATIONS Journal of Geophysical Research: Space Physics RESEARCH ARTICLE MESSENGER observations of large dayside flux 10.1002/2014JA019884 transfer events: Do they drive Mercury’s Key Points: substorm cycle? • Statistical study of dayside FTEs at Mercury Suzanne M. Imber1,2, James A. Slavin1, Scott A. Boardsen3,4, Brian J. Anderson5, Haje Korth5, • fi FTEs at Mercury have core elds of 5 6,7 approximately a few hundred nT Ralph L. McNutt Jr. , and Sean C. Solomon – and durations ~2 3s 1 2 • FTEs transport ~30% of the flux needed Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan, USA, Department to drive Mercury’ssubstormcycle of Physics and Astronomy, University of Leicester, Leicester, UK, 3Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA, 4Goddard Planetary Heliophysics Institute, University of Maryland, Baltimore County, Catonsville, Maryland, USA, 5The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA, 6Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, District of Columbia, USA, 7Lamont-Doherty Correspondence to: S. M. Imber, Earth Observatory, Columbia University, Palisades, New York, USA [email protected] Abstract The large-scale dynamic behavior of Mercury’s highly compressed magnetosphere is predominantly Citation: powered by magnetic reconnection, which transfers energy and momentum from the solar wind to the Imber, S. M., J. A. Slavin, S. A. Boardsen, fl B. J. Anderson, H. Korth, R. L. McNutt Jr., magnetosphere. The contribution of ux transfer events (FTEs) at the dayside magnetopause to the redistribution and S. C. Solomon (2014), MESSENGER of magnetic flux in Mercury’s magnetosphere is assessed with magnetic fielddataacquiredinorbitabout observations of large dayside flux Mercury by the Magnetometer on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging transfer events: Do they drive Mercury’s fi fi substorm cycle?, J. -
The Scientific Foundations of Forecasting Magnetospheric Space
Space Sci Rev DOI 10.1007/s11214-017-0399-8 The Scientific Foundations of Forecasting Magnetospheric Space Weather J.P. Eastwood1 · R. Nakamura2 · L. Turc3 · L. Mejnertsen1 · M. Hesse4 Received: 29 March 2017 / Accepted: 7 July 2017 © The Author(s) 2017. This article is published with open access at Springerlink.com Abstract The magnetosphere is the lens through which solar space weather phenomena are focused and directed towards the Earth. In particular, the non-linear interaction of the solar wind with the Earth’s magnetic field leads to the formation of highly inhomogenous electrical currents in the ionosphere which can ultimately result in damage to and problems with the operation of power distribution networks. Since electric power is the fundamental cornerstone of modern life, the interruption of power is the primary pathway by which space weather has impact on human activity and technology. Consequently, in the context of space weather, it is the ability to predict geomagnetic activity that is of key importance. This is usually stated in terms of geomagnetic storms, but we argue that in fact it is the substorm phenomenon which contains the crucial physics, and therefore prediction of substorm oc- currence, severity and duration, either within the context of a longer-lasting geomagnetic storm, but potentially also as an isolated event, is of critical importance. Here we review the physics of the magnetosphere in the frame of space weather forecasting, focusing on recent results, current understanding, and an assessment of probable future developments. Keywords Space weather · Magnetosphere · Geomagnetic storm · Substorm · Computer simulation The Scientific Foundation of Space Weather Edited by Rudolf von Steiger, Daniel Baker, André Balogh, Tamás Gombosi, Hannu Koskinen and Astrid Veronig B J.P. -
Energetic Particles in the Jovian Magnetosphere and Their Relation to Auroral Emissions
Energetic Particles in the Jovian magnetosphere and their relation to auroral emissions Von der Fakultat¨ fur¨ Physik und Geowissenchaften der Technischen Universitat¨ Carolo-Wilhelmina zu Braunschweig zur Erlangung des Grades einer Doktorin der Naturwissenschaften (Dr.rer.nat.) genehmigte Dissertation von Ana Teresa Monteiro Tomas´ aus Lisboa/Portugal Bibliografische Information Der Deutschen Bibliothek Die Deutsche Bibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet uber¨ http://dnb.ddb.de abrufbar. 1. Referentin oder Referent: Prof. Dr. K.-H. Glassmeier 2. Referentin oder Referent: Prof. Dr. M. K. Dougherty eingereicht am: 4 Februar 2005 mundliche¨ Prufung¨ (Disputation) am: 10 Mai 2005 Copyright c Copernicus GmbH 2005 ISBN 3-936586-39-X Copernicus GmbH, Katlenburg-Lindau Druck: Schaltungsdienst Lange, Berlin Printed in Germany Vorveroffentlichungen¨ der Dissertation Teilergebnisse aus dieser Arbeit wurden mit Genehmigung der Gemeinsamen Naturwis- senschaftlichen Fakult¨at, vertreten durch den Mentor oder den Betreuer der Arbeit, in folgenden Beitr¨agen vorab ver¨offentlicht: Publikationen Tomas, ´ A., J. Woch, N. Krupp, A. Lagg, K.-H. Glassmeier, M. K. Dougherty and P. G. Hanlon, Changes of the energetic particle characteristics in the inner part of the Jovian magnetosphere: a topological study. Planet. Space Sci., 52, 491-498, 2004. Tomas, ´ A., J. Woch, N. Krupp, A. Lagg, K.-H. Glassmeier and W. S. Kurth, Ener- getic electrons in the inner part of the Jovian magnetosphere and their relation to auroral emissions. J. Geophys. Res., 109, A06203, doi:10.1029/2004JA010405, 2004. Woch, J., N. Krupp, A. Lagg and A. Tom´as, The structure and dynamics of the Jovian energetic particle distribution.