Author: "Lockheed Martin Advanced Technology Center (ATC)" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Lockheed Martin Advanced Technology Center (ATC)"' showing total 30 results

Start Over Author "Lockheed Martin Advanced Technology Center (ATC)"

30 results on '"Lockheed Martin Advanced Technology Center (ATC)"'

1. ROSINA/DFMS and IES observations of 67P: Ion-neutral chemistry in the coma of a weakly outgassing comet

Author: André Bieler, M. Rinaldi, Martin Rubin, Michael R. Combi, Thierry Sémon, Kathrin Altwegg, J. H. Waite, Hans Balsiger, Jean-Jacques Berthelier, Stephen A. Fuselier, J. De Keyser, Myrtha Hässig, Chia-Yu Tzou, C. Briois, Peter Wurz, Herbert Gunell, Henri Rème, Kirk C. Hansen, Susarla Raghuram, Ulrich Mall, Gaël Cessateur, M. Galand, S. M. Petrinec, Annette Jäckel, A. Korth, James L. Burch, K. J. Trattner, E. Vigren, B. Fiethe, Tamas I. Gombosi, Kathleen Mandt, Léna Le Roy, T. W. Broiles, Ursina Calmonte, Sébastien Gasc, Space Science Division [San Antonio], Southwest Research Institute [San Antonio] ( SwRI ), UTSA Department of Physics and Astronomy [San Antonio], The University of Texas at San Antonio ( UTSA ), Physikalisches Institut [Bern], Universität Bern [Bern], IMPEC - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales ( LATMOS ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] ( AOSS ), University of Michigan [Ann Arbor], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Centre National de la Recherche Scientifique ( CNRS ) -Université d'Orléans ( UO ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique ( BIRA-IASB ), Institute of Computer and Network Engineering [Braunschweig] ( IDA ), Technische Universität Braunschweig [Braunschweig], Imperial College London, Max Planck Institute for Solar System Research ( MPS ), Lockheed Martin Advanced Technology Center ( ATC ), Institut de recherche en astrophysique et planétologie ( IRAP ), Université Paul Sabatier - Toulouse 3 ( UPS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratory for Atmospheric and Space Physics [Boulder] ( LASP ), University of Colorado Boulder [Boulder], Swedish Institute of Space Physics [Uppsala] ( IRF ), Southwest Research Institute [San Antonio] (SwRI), The University of Texas at San Antonio (UTSA), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan System-University of Michigan System, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Institute of Computer and Network Engineering [Braunschweig] (IDA), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Lockheed Martin Advanced Technology Center (ATC), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Swedish Institute of Space Physics [Uppsala] (IRF), Universität Bern [Bern] (UNIBE), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: 67P/Churyumov-Gerasimenko, DYNAMICS, Comet, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Data analysis, Coma (optics), Astrophysics, Astronomy & Astrophysics, MASS, Mass spectrometry, Chemical reaction, Ion, METHANE, Comet nucleus, SPECTROMETER, comets, RATES, HALLEY, AMMONIA, Science & Technology, Chemistry, comets: individual: 67P/Churyumov-Gerasimenko, Astronomy and Astrophysics, SENSOR, plasmas, [ SDU.ASTR.EP ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], methods: data analysis, Outgassing, Solar wind, molecular processes, 0201 Astronomical And Space Sciences, solar wind, INNER COMA, 13. Climate action, Space and Planetary Science, Physical Sciences, P/HALLEY
Abstract: International audience; The Rosetta encounter with comet 67P/Churyumov-Gerasimenko provides a unique opportunity for an in situ, up-close investigation of ion-neutral chemistry in the coma of a weakly outgassing comet far from the Sun.Observations of primary and secondary ions and modeling are used to investigate the role of ion-neutral chemistry within the thin coma.Methods. Observations from late October through mid-December 2014 show the continuous presence of the solar wind 30 km from the comet nucleus. These and other observations indicate that there is no contact surface and the solar wind has direct access to the nucleus. On several occasions during this time period, the Rosetta/ROSINA/Double Focusing Mass Spectrometer measured the low-energy ion composition in the coma. Organic volatiles and water group ions and their breakup products (masses 14 through 19), CO2+ (masses 28 and 44) another mass peaks (at masses 26, 27 , and possibly 30) were observed. Secondary ions include H3O+ and HCO+ (masses 19 and 29). These secondary ions indicate ion-neutral chemistry in the thin coma of the comet. A relatively simple model is constructed to account for the low H3O+/H2O+ and HCO+/CO+ ratios observed in a water dominated coma. Results from this simple model are compared with results from models that include a more detailed chemical reaction network.At low outgassing rates, predictions from the simple model agree with observations and with results from more complex models that include much more chemistry. At higher outgassing rates, the ion-neutral chemistry is still limited and high HCO+/CO+ ratios are predicted and observed. However, at higher outgassing rates, the model predicts high H3O+/H2O+ ratios and the observed ratios are often low. These low ratios may be the result of the highly heterogeneous nature of the coma, where CO and CO2 number densities can exceed that of water.
Published: 2015
Full Text: View/download PDF

2. Ion chemistry in the coma of comet 67P near perihelion

Author: Martin Rubin, Michael G. Rinaldi, J. De Keyser, Peter Wurz, Michael R. Combi, Stephen A. Fuselier, Thierry Sémon, Kathrin Altwegg, Kirk C. Hansen, Ulrich Mall, Myrtha Hässig, Erik Vigren, B. Fiethe, Jean-Jacques Berthelier, C. Y. Tzou, Tamas I. Gombosi, Gaël Cessateur, H. Rème, C. Briois, Léna Le Roy, J. H. Waite, James L. Burch, Arnaud Beth, Hans Balsiger, Karlheinz Trattner, S. M. Petrinec, André Bieler, Kathleen Mandt, Marina Galand, Herbert Gunell, K. L. Heritier, Ursina Calmonte, Adrienn Luspay-Kuti, A. Korth, T. W. Broiles, Sébastien Gasc, Space Science Division [San Antonio], Southwest Research Institute [San Antonio] ( SwRI ), UTSA Department of Physics and Astronomy [San Antonio], The University of Texas at San Antonio ( UTSA ), Physikalisches Institut [Bern], Universität Bern [Bern], IMPEC - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales ( LATMOS ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Physics [London], Imperial College London, Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] ( AOSS ), University of Michigan [Ann Arbor], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS ), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique ( BIRA-IASB ), Institute of Computer and Network Engineering [Braunschweig] ( IDA ), Technische Universität Braunschweig [Braunschweig], Max-Planck-Institut für Sonnensystemforschung ( MPS ), Lockheed Martin Advanced Technology Center ( ATC ), Institut de recherche en astrophysique et planétologie ( IRAP ), Université Paul Sabatier - Toulouse 3 ( UPS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratory for Atmospheric and Space Physics [Boulder] ( LASP ), University of Colorado Boulder [Boulder], Swedish Institute of Space Physics [Uppsala] ( IRF ), Southwest Research Institute [San Antonio] (SwRI), The University of Texas at San Antonio (UTSA), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Physics [Imperial College London], Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan System-University of Michigan System, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Institute of Computer and Network Engineering [Braunschweig] (IDA), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Lockheed Martin Advanced Technology Center (ATC), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Swedish Institute of Space Physics [Uppsala] (IRF), Universität Bern [Bern] (UNIBE), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Science and Technology Facilities Council (STFC)
Subjects: 010504 meteorology & atmospheric sciences, 530 Physics, individual [comets], Comet, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Coma (optics), Astrophysics, Equinox, Astronomy & Astrophysics, Mass spectrometry, 01 natural sciences, Ion, general [comets], Fusion, plasma och rymdfysik, Comet nucleus, 0103 physical sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, 520 Astronomy, Astronomy, Astronomy and Astrophysics, Plasma, 620 Engineering, plasmas, Fusion, Plasma and Space Physics, [ SDU.ASTR.EP ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 0201 Astronomical And Space Sciences, Solar wind, solar wind, 13. Climate action, Space and Planetary Science
Abstract: The ESLAB 50 Symposium - spacecraft at comets from 1P/Halley to 67P/Churyumov-Gerasimenko; International audience; The coma and the comet-solar wind interaction of comet 67P/Churyumov-Gerasimenko changed dramatically from the initial Rosetta spacecraft encounter in August 2014 through perihelion in August 2015. Just before equinox (at 1.6 AU from the Sun), the solar wind signal disappeared and two regions of different cometary ion characteristics were observed. These “outer” and “inner” regions have cometary ion characteristics similar to outside and inside the ion pileup region observed during the Giotto approach to comet 1P/Halley. Rosetta/DFMS ion mass spectrometer observations are used here to investigate the H3O+/H2O+ ratio in the outer and inner regions at 67P/ Churyumov-Gerasimenko. The H3O+/H2O+ ratio and the H3O+ signal are observed to increase in the transition from the outer to the inner region and the H3O+ signal appears to be weakly correlated with cometary ion energy. These ion composition changes are similar to the ones observed during the 1P/Halley flyby. Modeling is used to determine the importance of neutral composition and transport of neutrals and ions away from the nucleus. This modeling demonstrates that changes in the H3O+/H2O+ ratio appear to be driven largely by transport properties and only weakly by neutral composition in the coma.
Published: 2016
Full Text: View/download PDF

3. Dual storage and release of molecular oxygen in comet 67P/Churyumov-Gerasimenko

Author: Adrienn Luspay-Kuti, Olivier Mousis, Françoise Pauzat, Ozge Ozgurel, Yves Ellinger, Jonathan I. Lunine, Stephen A. Fuselier, Kathleen E. Mandt, Karlheinz J. Trattner, Steven M. Petrinec, Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Centre National d'Etudes Spatiales - Direction Des Lanceurs. (CNES), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie théorique (LCT), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Cornell University [New York], The University of Texas at San Antonio (UTSA), Southwest Research Institute [San Antonio] (SwRI), University of Colorado [Boulder], Lockheed Martin Advanced Technology Center (ATC), National Aeronautics and Space Administration (NASA) [80NSSC18K1620], Excellence Initiative of Aix-Marseille Universite-A*M idex, a French 'Investissements d'Avenir programme' French National Research Agency (ANR) [AMX-21-IET-018], CNES Centre National D'etudes Spatiales, NASA National Aeronautics and Space Administration (NASA) [NNX17AL71A], CNRS-INSU Centre National de la Recherche Scientifique (CNRS), and ANR-11-IDEX-0001,Amidex,INITIATIVE D'EXCELLENCE AIX MARSEILLE UNIVERSITE(2011)
Subjects: [CHIM]Chemical Sciences, Astronomy and Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: All data processed as described above are included in the Article and Supplementary Information. The ROSINA/DFMS spectra used to derive count rates are available in the NASA Planetary DataSystem (https://pds-smallbodies.astro.umd.edu/data_sb/missions/rosetta/index.shtml) and ESA Planetary Science Archive (https://archives.esac.esa.int/psa/#!Table%20View/Rosetta=mission). Source data are provided with this paper.; International audience; One of the biggest surprises of the Rosetta mission was the detection of O-2 in the coma of 67P/Churyumov-Gerasimenko in remarkably high abundances. The measured levels of O-2 in the coma are generally assumed to reflect the overall abundance and chemical origin of cometary O-2 in the nucleus. Along with its strong association with H2O and weak association with CO and CO2, these measurements led to the consensus that the source and release of cometary O-2 are linked to H2O. We analysed ROSINA observations and found a previously unrecognized change in the correlations of O-2 with H2O, CO2 and CO that contradicts the prevailing notion that the release of O-2 is linked to H2O at all times. These findings can be explained by the presence of two distinct reservoirs of O-2: a pristine source in the deeper nucleus layers dating back to before nucleus formation, and an H2O-trapped secondary reservoir formed during the thermal evolution of the nucleus. These results imply that O-2 must have been incorporated into the nucleus in a solid and distinct phase during accretion in significantly lower abundances than previously assumed. Seasonal changes in the correlation between O-2 and H2O in comet 67P's coma are indicative of two reservoirs of molecular oxygen in the nucleus, a deeper primordial one and a surficial one, suggesting that the observed high abundance of O-2 and its association with H2O are not reflective of the original accretion source.
Published: 2022
Full Text: View/download PDF

4. Changes in granulation scales over the solar cycle seen with SDO/HMI and Hinode/SOT

Author: Jérôme Ballot, J. M. Malherbe, Z. Frank, Th. Roudier, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Lockheed Martin Solar and Astrophysics Laboratory (LMSAL), Lockheed Martin Advanced Technology Center (ATC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
Subjects: Convection, 010504 meteorology & atmospheric sciences, Granule (solar physics), FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, Sun: granulation, Granulation, Sun: activity, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, integumentary system, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], food and beverages, Astronomy and Astrophysics, Solar maximum, Solar cycle, Astrophysics - Solar and Stellar Astrophysics, Convection zone, 13. Climate action, Space and Planetary Science, Physics::Space Physics, Maximum density, Astrophysics::Earth and Planetary Astrophysics
Abstract: The Sun is the only star where the superficial turbulent convection can be observed at very high spatial resolution. The Solar Dynamics Observatory (SDO) has continuously observed the full Sun from space with multi-wavelength filters since July 2010. In particular, the Helioseismic and Magnetic Imager (HMI) instrument takes high-cadence frames (45 seconds) of continuum intensity in which solar granulation is visible. We aimed to follow the evolution of the solar granules over an activity cycle and look for changes in their spatial properties. We investigated the density of granules and their mean area derived directly from the segmentation of deconvolved images from SDO/HMI. To perform the segmentation, we define granules as convex elements of images. We measured an approximately 2% variation in the density and the mean area of granules over the cycle, the density of granules being greater at solar maximum with a smaller granule mean area. The maximum density appears to be delayed by about one year compared to classical activity indicators, such as the sunspot number. We complemented this study with high-spatial-resolution observations obtained with Hinode/SOTBFI (Solar Optical Telescope Broadband Filter Imager), which are consistent with our results. The observed variations in solar granulation at the disc centre reveal a direct insight into the change in the physical properties that occur in the upper convective zone during a solar cycle. These variations can be due to interactions between convection and magnetic fields, either at the global scale or, locally, at the granulation scale., Comment: 10 pages, 17 figures, accepted for publication in Astronomy and Astrophysics
Published: 2021
Full Text: View/download PDF

5. On the Ubiquity of Magnetic Reconnection Inside Flux Transfer Event‐Like Structures at the Earth's Magnetopause

Author: Michael O. Chandler, Elena Grigorenko, S. M. Petrinec, Hiroshi Hasegawa, Charlie J. Farrugia, Victoria N. Coffey, W. R. Paterson, C. Schiff, John C. Dorelli, Thomas E. Moore, Marit Øieroset, S. Fadanelli, K. J. Trattner, Sergio Toledo-Redondo, Jonathan Eastwood, S. A. Fuselier, T. D. Phan, C. J. Pollock, J. A. Sauvaud, Benoit Lavraud, Yoshitaka Saito, Q. Lenouvel, C. Jacquey, Philippe Garnier, James L. Burch, D. J. Gershman, R. Kieokaew, N. Fargette, D. L. A. Avanov, S. E. Smith, Vincent Génot, Emmanuel Penou, Barbara L. Giles, Science and Technology Facilities Council (STFC), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley], University of California-University of California, Centre de physique moléculaire optique et hertzienne (CPMOH), Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1, Space Science Division [San Antonio], Southwest Research Institute [San Antonio] (SwRI), Lockheed Martin Advanced Technology Center (ATC), Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), Laboratoire de microbiologie et génétique moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), Laboratoire de Parasitologie-Mycologie, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), NASA Headquarters, Space Research Institute of the Russian Academy of Sciences (IKI), Russian Academy of Sciences [Moscow] (RAS), Hokkaido University [Sapporo, Japan], Centre d'Immunologie de Marseille - Luminy (CIML), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Joint Global Change Research Institute, Pacific Northwest National Laboratory (PNNL)-University of Maryland [College Park], University of Maryland System-University of Maryland System, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Université Sciences et Technologies - Bordeaux 1 (UB)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de microbiologie et génétique moléculaires - UMR5100 (LMGM), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and Génot, Vincent
Subjects: Physics, 010504 meteorology & atmospheric sciences, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Magnetic reconnection, Geophysics, 01 natural sciences, Physics::Space Physics, 0103 physical sciences, Meteorology & Atmospheric Sciences, General Earth and Planetary Sciences, Magnetopause, Flux transfer event, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Earth (classical element), 0105 earth and related environmental sciences
Abstract: Flux transfer events (FTEs) are transient phenomena frequently observed at the Earth's magnetopause. Their usual interpretation is a flux rope moving away from the reconnection region. However, the Magnetospheric Multiscale Mission revealed that magnetic reconnection sometimes occurs inside these structures, questioning their flux rope configuration. Here we investigate 229 FTE‐type structures and find reconnection signatures inside 19% of them. We analyze their large‐scale magnetic topology using electron heat flux and find that it is significantly different across the FTE reconnecting current sheets, demonstrating that they are constituted of two magnetically disconnected structures. We also find that the interplanetary magnetic field (IMF) associated with reconnecting FTEs presents a strong By component. We discuss several formation mechanisms to explain these observations. In particular, the maximum magnetic shear model predicts that for large IMF By, two spatially distinct X lines coexist at the magnetopause. They can generate separate magnetic flux tubes that may become interlaced.
Published: 2020
Full Text: View/download PDF

6. Mass Loading the Earth's Dayside Magnetopause Boundary Layer and Its Effect on Magnetic Reconnection

Author: Paul Tenfjord, Robert J. Strangeway, Daniel B. Graham, Stein Haaland, Thomas E. Moore, S. A. Fuselier, Benoit Lavraud, Michael Hesse, Wenya Li, James L. Burch, Sarah K. Vines, K. J. Trattner, Jérémy Dargent, S. M. Petrinec, Mats André, Katariina Nykyri, Alex Glocer, Sergio Toledo-Redondo, C. R. Chappell, L. M. Kistler, Michael H. Denton, N. Aunai, L. Alm, Lockheed Martin Advanced Technology Center (ATC), European Space Agency (ESA), Swedish Institute of Space Physics [Uppsala] (IRF), Laboratoire de Physique des Plasmas (LPP), Université Paris-Saclay-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École polytechnique (X)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Max-Planck-Institut für Extraterrestrische Physik (MPE), NASA Goddard Space Flight Center (GSFC), EOS Space Science Center [Durham], University of New Hampshire (UNH), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), CFD Lab [Montréal], Department of Mechanical Engineering [Montréal], McGill University = Université McGill [Montréal, Canada]-McGill University = Université McGill [Montréal, Canada], Agence Spatiale Européenne = European Space Agency (ESA), Université Paris-Sud - Paris 11 (UP11)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, 010504 meteorology & atmospheric sciences, Field line, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Magnetic reconnection, 010502 geochemistry & geophysics, 01 natural sciences, Computational physics, Magnetic field, Boundary layer, Geophysics, Magnetosheath, Physics::Plasma Physics, Physics::Space Physics, General Earth and Planetary Sciences, Magnetopause, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Ionosphere, Interplanetary magnetic field, 0105 earth and related environmental sciences
Abstract: International audience; When the interplanetary magnetic field is northward for a period of time, O + from the high-latitude ionosphere escapes along reconnected magnetic field lines into the dayside magnetopause boundary layer. Dual-lobe reconnection closes these field lines, which traps O + and mass loads the boundary layer. This O + is an additional source of magnetospheric plasma that interacts with magnetosheath plasma through magnetic reconnection. This mass loading and interaction is illustrated through analysis of a magnetopause crossing by the Magnetospheric Multiscale spacecraft. While in the O +-rich boundary layer, the interplanetary magnetic field turns southward. As the Magnetospheric Multiscale spacecraft cross the high-shear magnetopause, reconnection signatures are observed. While the reconnection rate is likely reduced by the mass loading, reconnection is not suppressed at the magnetopause. The high-latitude dayside ionosphere is therefore a source of magnetospheric ions that contributes often to transient reduction in the reconnection rate at the dayside magnetopause.
Published: 2019
Full Text: View/download PDF

7. Comparison of neutral outgassing of comet 67P/Churyumov-Gerasimenko inbound and outbound beyond 3 AU from ROSINA/DFMS

Author: S. M. Petrinec, S. A. Fuselier, O. Mousis, Urs Mall, Arnaud Beth, Jean-Jacques Berthelier, Kathleen Mandt, K. J. Trattner, Myrtha Hässig, George Livadiotis, Peter Wurz, B. Fiethe, Tamas I. Gombosi, Adrienn Luspay-Kuti, Kirk C. Hansen, Chia-Yu Tzou, Kathrin Altwegg, Frederik Dhooghe, Martin Rubin, Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Physikalisches Institut [Bern], Universität Bern [Bern], Center for Space and Habitability (CSH), University of Bern, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Physics [Imperial College London], Imperial College London, Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Centre for Mathematical Plasma-Astrophysics [Leuven] (CmPA), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Institute of Computer and Network Engineering [Braunschweig] (IDA), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Southwest Research Institute [San Antonio] (SwRI), Department of Climate and Space Sciences and Engineering (CLaSP), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Lockheed Martin Advanced Technology Center (ATC), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Universität Bern [Bern] (UNIBE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)
Subjects: Insolation, Physics, 010504 meteorology & atmospheric sciences, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 520 Astronomy, Comet, Astronomy and Astrophysics, Context (language use), Coma (optics), Equinox, Astrophysics, 620 Engineering, 01 natural sciences, Article, On board, Outgassing, 13. Climate action, Space and Planetary Science, 0103 physical sciences, 010303 astronomy & astrophysics, Southern Hemisphere, 0105 earth and related environmental sciences
Abstract: Context.Pre-equinox measurements of comet 67P/Churyumov-Gerasimenko with the mass spectrometer ROSINA/DFMS on board the Rosetta spacecraft revealed a strongly heterogeneous coma. The abundances of major and various minor volatile species were found to depend on the latitude and longitude of the nadir point of the spacecraft. The observed time variability of coma species remained consistent for about three months up to equinox. The chemical variability could be generally interpreted in terms of surface temperature and seasonal effects superposed on some kind of chemical heterogeneity of the nucleus.Aims.We compare here pre-equinox (inbound) ROSINA/DFMS measurements from 2014 to measurements taken after the outbound equinox in 2016, both at heliocentric distances larger than 3 AU. For a direct comparison we limit our observations to the southern hemisphere.Methods.We report the similarities and differences in the concentrations and time variability of neutral species under similar insolation conditions (heliocentric distance and season) pre- and post-equinox, and interpret them in light of the previously published observations. In addition, we extend both the pre- and post-equinox analysis by comparing species concentrations with a mixture of CO2and H2O.Results.Our results show significant changes in the abundances of neutral species in the coma from pre- to post-equinox that are indicative of seasonally driven nucleus heterogeneity.Conclusions.The observed pre- and post-equinox patterns can generally be explained by the strong erosion in the southern hemisphere that moves volatile-rich layers near the surface.
Published: 2019
Full Text: View/download PDF

8. Nonlobe Reconnection at the Earth's Magnetopause for Northward IMF

Author: K. J. Trattner, S. M. Petrinec, S. A. Fuselier, J. Mukherjee, Benoit Lavraud, Lockheed Martin Advanced Technology Laboratories (ATL), Lockheed Martin Advanced Technology Laboratories, Lockheed Martin Advanced Technology Center (ATC), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, 010504 meteorology & atmospheric sciences, Field line, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Magnetosphere, Magnetic reconnection, Geophysics, 010502 geochemistry & geophysics, 01 natural sciences, Solar wind, Current sheet, Magnetosheath, Space and Planetary Science, Physics::Space Physics, Magnetopause, Astrophysics::Solar and Stellar Astrophysics, Interplanetary magnetic field, 0105 earth and related environmental sciences
Abstract: International audience; Under northward interplanetary magnetic field conditions, magnetic reconnection at the Earth's magnetopause is usually thought to operate through the merging of magnetosheath magnetic field lines and open magnetic field lines from the magnetospheric lobe. However, reconnection also occurs between magnetosheath field lines and closed magnetic field lines in the magnetosphere. Under certain conditions, this nonlobe field line reconnection has distinct plasma and magnetic field signatures that distinguish it from reconnection of lobe field lines. A survey of these conditions suggests that nonlobe reconnection at the Earth's magnetopause may be common even for relatively strong northward IMF. Plain Language Summary Magnetic reconnection interconnects magnetic field lines across a current sheet like that at the Earth's magnetopause or like that in the solar corona. This paper describes a type of interconnection of magnetic field lines at the magnetopause that was first reported for the solar corona. It appears that this type of reconnection is fairly common at the magnetopause. The different topology of this reconnection suggests a different type of interaction between the magnetic field lines in the solar wind and the field lines of the Earth.
Published: 2018
Full Text: View/download PDF

9. Solar Ultraviolet Bursts

Author: Shin Toriumi, Chris J. Nelson, Luc Rouppe van der Voort, Kevin Reardon, Hardi Peter, Peter R. Young, Maria S. Madjarska, Sanja Danilovic, Petr Heinzel, Brigitte Schmieder, Gregal J. M. Vissers, Zhenghua Huang, Lakshmi Pradeep Chitta, Yukio Katsukawa, A. Berlicki, Robert J. Rutten, C. A. Madsen, Mark C. M. Cheung, Hui Tian, Centre for Research on Environmental Systems and Statistics (CRES), Lancaster University, Shandong Agricultural University (SDAU), Observatoire de Paris - Site de Paris (OP), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), School of Earth and Space Sciences [Beijing], Peking University [Beijing], Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Institute of Theoretical Astrophysics [Oslo], University of Oslo (UiO), Astrophysics Research Centre [Belfast] (ARC), Queen's University [Belfast] (QUB), Albanova University Centre, National Astronomical Observatory of Japan (NAOJ), Astronomical Institute [Wroclaw], University of Wrocław [Poland] (UWr), Lockheed Martin Solar and Astrophysics Laboratory (LMSAL), Lockheed Martin Advanced Technology Center (ATC), Harvard-Smithsonian Center for Astrophysics (CfA), Smithsonian Institution-Harvard University [Cambridge], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, FEATURES, Flux, Astrophysics, medicine.disease_cause, 01 natural sciences, transition region [Sun], MAGNETIC RECONNECTION, Astrophysics::Solar and Stellar Astrophysics, activity [Sun], Sun: transition region, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, EXPLOSIVE EVENTS, [PHYS]Physics [physics], Physics, Astrophysics - Solar and Stellar Astrophysics, Physical Sciences, Physics::Space Physics, SI-IV, Space Science, atmosphere [Sun], H-ALPHA, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy & Astrophysics, Atmosphere, ELLERMAN BOMBS, Sun: activity, 0103 physical sciences, medicine, Solar and Stellar Astrophysics (astro-ph.SR), TRANSITION-REGION BLINKERS, 0105 earth and related environmental sciences, UV radiation [Sun], Photosphere, Sunspot, Science & Technology, Astronomy and Astrophysics, Magnetic reconnection, IV BURSTS, Sun: UV radiation, Planetary science, QUIET-SUN, 13. Climate action, Space and Planetary Science, EMERGING FLUX, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Sun: atmosphere, Ultraviolet
Abstract: The term "ultraviolet (UV) burst" is introduced to describe small, intense, transient brightenings in ultraviolet images of solar active regions. We inventorize their properties and provide a definition based on image sequences in transition-region lines. Coronal signatures are rare, and most bursts are associated with small-scale, canceling opposite-polarity fields in the photosphere that occur in emerging flux regions, moving magnetic features in sunspot moats, and sunspot light bridges. We also compare UV bursts with similar transition-region phenomena found previously in solar ultraviolet spectrometry and with similar phenomena at optical wavelengths, in particular Ellerman bombs. Akin to the latter, UV bursts are probably small-scale magnetic reconnection events occurring in the low atmosphere, at photospheric and/or chromospheric heights. Their intense emission in lines with optically thin formation gives unique diagnostic opportunities for studying the physics of magnetic reconnection in the low solar atmosphere. This paper is a review report from an International Space Science Institute team that met in 2016-2017., Review article accepted for publication in Space Science Reviews
Published: 2018
Full Text: View/download PDF

10. Two sources of magnetosheath ions observed by Cluster in the mid-altitude polar cusp

Author: C. P. Escoubet, Andrew Fazakerley, Matthew Taylor, M. W. Dunlop, Arnaud Masson, Frederic Pitout, H. E. Laakso, C. Vallat, H. Rème, J. M. Bosqued, Jean Berchem, Karlheinz Trattner, Iannis Dandouras, European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Extraterrestrische Physik (MPE), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), and University College of London [London] (UCL)
Subjects: Atmospheric Science, 010504 meteorology & atmospheric sciences, Mathematics::Number Theory, Population, Aerospace Engineering, Magnetosphere, Subsolar point, Astrophysics, Atmospheric sciences, 01 natural sciences, Magnetosheath, 0103 physical sciences, Interplanetary magnetic field, education, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, education.field_of_study, Astronomy and Astrophysics, Magnetic reconnection, Magnetopause, Geophysics, 13. Climate action, Space and Planetary Science, Magnetospheric physics, Physics::Space Physics, General Earth and Planetary Sciences, Cusp (anatomy), Cusp and boundary layers
Abstract: International audience; Double cusps have been observed on a few occasions by polar orbiting spacecraft and ground-based observatories. The four Cluster spacecraft observed two distinct regions, showing characteristics of a double cusp, during a mid-altitude cusp pass on 7 August 2004. The Wind spacecraft detected a southward turning of the Interplanetary Magnetic Field (IMF) at the beginning of the cusp crossings and IMF-Bz stayed negative throughout. Cluster 4 observed a high energy step in the ion precipitation around 1 keV on the equatorward side of the cusp and a dense ion population in the cusp centre. Cluster 1, entering the cusp around 1 min later, observed only a partial ion dispersion with a low energy cutoff reaching 100 eV, together with the dense ion population in the cusp centre. About 9 min later, Cluster 3 entered the cusp and observed full ion dispersion from a few keV down to around 50 eV, together with the dense ion population in the centre of the cusp. The ion flow was directed poleward and eastward in the step/dispersion, whereas in the centre of the cusp the flow was directed poleward and westward. In addition the altitude of the source region of ion injection in the step/dispersion was found 50% larger than in the cusp centre. This event could be explained by the onset of dayside reconnection when the IMF turned southward. The step would be the first signature of component reconnection near the subsolar point, and the injection in the centre of the cusp a result of anti-parallel reconnection in the northern dusk side of the cusp. A three-dimensional magnetohydrodynamic (MHD) simulation is used to display the topology of the magnetic field and locate the sources of the ions during the event.
Published: 2008
Full Text: View/download PDF

11. Rosina – Rosetta Orbiter Spectrometer for Ion and Neutral Analysis

Author: T Magoncelli, E. G. Shelley, Jenny Müller, E. Arijs, Christian Mazelle, Peter Bochsler, C. Aoustin, J. M. Illiano, Timm-Emanuel Riesen, H. Lauche, A. Loose, Stefano Livi, B. Fiethe, Tamas I. Gombosi, J. De Keyser, J. Fischer, Stephan Graf, Lennard A. Fisk, H. Rème, J. L. Medale, Jean-Jacques Berthelier, S. Scherer, Hermann Wollnik, Bruce P. Block, Peter Wurz, Annette Jäckel, Sandra Wüthrich, Kathrin Altwegg, Jean-André Sauvaud, S. Delanoye, U. Langer, Eernest Kopp, Eddy Neefs, D. T. Young, Fritz Gliem, Jean-Loup Bertaux, A. G. Ghielmetti, J. H. Waite, D. Nevejans, B. Wilken, A. Korth, M. Mildner, L. Duvet, Martin Rubin, Hans Balsiger, Peter Eberhardt, K Heerlein, G. R. Carignan, Stephen A. Fuselier, Ulrich Mall, Physikalisches Institut [Bern], Universität Bern [Bern], Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Space Physics Research Laboratory [Ann Arbor] (SPRL), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Southwest Research Institute [San Antonio] (SwRI), Physikalisches Institut [Gießen], Justus-Liebig-Universität Gießen (JLU), Universität Bern [Bern] (UNIBE), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), and Justus-Liebig-Universität Gießen = Justus Liebig University (JLU)
Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Physics, 010504 meteorology & atmospheric sciences, Spectrometer, Comet, Astronomy and Astrophysics, Mass spectrometry, 7. Clean energy, 01 natural sciences, Ion, law.invention, Astrobiology, Nuclear physics, Orbiter, Planetary science, Fragmentation (mass spectrometry), 13. Climate action, Space and Planetary Science, law, 0103 physical sciences, Formation and evolution of the Solar System, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) will answer important questions posed by the mission's main objectives. After Giotto, this will be the first time the volatile part of a comet will be analyzed in situ. This is a very important investigation, as comets, in contrast to meteorites, have maintained most of the volatiles of the solar nebula. To accomplish the very demanding objectives through all the different phases of the comet's activity, ROSINA has unprecedented capabilities including very wide mass range (1 to >300 amu), very high mass resolution (m/Δ m > 3000, i.e. the ability to resolve CO from N2 and 13C from 12CH), very wide dynamic range and high sensitivity, as well as the ability to determine cometary gas velocities, and temperature. ROSINA consists of two mass spectrometers for neutrals and primary ions with complementary capabilities and a pressure sensor. To ensure that absolute gas densities can be determined, each mass spectrometer carries a reservoir of a calibrated gas mixture allowing in-flight calibration. Furthermore, identical flight-spares of all three sensors will serve for detailed analysis of all relevant parameters, in particular the sensitivities for complex organic molecules and their fragmentation patterns in our electron bombardment ion sources.
Published: 2007
Full Text: View/download PDF

12. Solar Magnetic Field Reversals and the Role of Dynamo Families

Author: Marc L. DeRosa, Allan Sacha Brun, J. T. Hoeksema, Lockheed Martin Solar and Astrophysics Laboratory (LMSAL), Lockheed Martin Advanced Technology Center (ATC), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Hansen Experimental Physics Lab [Stanford] (HEPL), Stanford University, STARS2, European Project: 207430,EC:FP7:ERC,ERC-2007-StG,STARS2(2008), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Hansen Experimental Physics Laboratory (HEPL), and Stanford University [Stanford]
Subjects: 010504 meteorology & atmospheric sciences, Polarity (physics), FOS: Physical sciences, Astrophysics, 7. Clean energy, 01 natural sciences, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Coupling, Physics, Solar observatory, Time evolution, Astronomy and Astrophysics, Magnetic field, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Dynamo theory, Physics::Space Physics, Harmonic, Astrophysics - Earth and Planetary Astrophysics, Dynamo
Abstract: The variable magnetic field of the solar photosphere exhibits periodic reversals as a result of dynamo activity occurring within the solar interior. We decompose the surface field as observed by both the Wilcox Solar Observatory and the Michelson Doppler Imager into its harmonic constituents, and present the time evolution of the mode coefficients for the past three sunspot cycles. The interplay between the various modes is then interpreted from the perspective of general dynamo theory, where the coupling between the primary and secondary families of modes is found to correlate with large-scale polarity reversals for many examples of cyclic dynamos. Mean-field dynamos based on the solar parameter regime are then used to explore how such couplings may result in the various long-term trends in the surface magnetic field observed to occur in the solar case., Comment: Accepted to ApJ; comments/corrections to this article are welcome via e-mail, even after publication
Published: 2013
Full Text: View/download PDF

13. How the inclination of Earth's orbit affects incoming solar irradiance

Author: Vieira, L.E.A., Norton, A, Dudok De Wit, Thierry, Kretzschmar, Matthieu, Schmidt, G.A., Cheung, M.C.M., Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), HEPL, Solar Physics, Stanford University, Solar Influences Data Analysis Center [Brussels] (SIDC), Royal Observatory of Belgium [Brussels] (ROB), NASA Goddard Institute for Space Studies (GISS), NASA Goddard Space Flight Center (GSFC), Lockheed Martin Solar and Astrophysics Laboratory (LMSAL), Lockheed Martin Advanced Technology Center (ATC), European Project: 261948,EC:FP7:SPA,FP7-SPACE-2010-1,ATMOP(2011), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES)
Subjects: [SDU]Sciences of the Universe [physics], Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics
Abstract: International audience; [1] The variability in solar irradiance, the main external energy source of the Earth's system, must be critically studied in order to place the effects of human-driven climate change into perspective and allow plausible predictions of the evolution of climate. Accurate measurements of total solar irradiance (TSI) variability by instruments onboard space platforms during the last three solar cycles indicate changes of approximately 0.1% over the sunspot cycle. Physics-based models also suggest variations of the same magnitude on centennial to millennia timescales. Additionally, long-term changes in Earth's orbit modulate the solar irradiance reaching the top of the atmosphere. Variations of orbital inclination in relation to the Sun's equator could potentially impact incoming solar irradiance as a result of the anisotropy of the distribution of active regions. Due to a lack of quantitative estimates, this effect has never been assessed. Here, we show that although observers with different orbital inclinations experience various levels of irradiance, modulations in TSI are not sufficient to drive observed 100 kyr climate variations. Based on our model we find that, due to orbital inclination alone, the maximum change in the average TSI over timescales of kyrs is $0.003 Wm À2 , much smaller than the $1.5 Wm À2 annually integrated change related to orbital eccentricity variations, or the 1–8 Wm À2 variability due to solar magnetic activity. Here, we stress that out-of-ecliptic measurements are needed in order to constrain models for the long-term evolution of TSI and its impact on climate. Citation: Vieira, L. E.
Published: 2012
Full Text: View/download PDF

14. Computer Vision for The Solar Dynamics Observatory

Author: Kelly E. Korreck, N.-E. Raouafi, Jean-François Hochedez, Manolis K. Georgoulis, S. Farid, A. Engell, Craig DeForest, Steven H. Saar, Thomas Wiegelmann, Yingna Su, Rafal A. Angryk, M. J. Wills-Davey, P. C. Grigis, R. Timmons, Antonia Savcheva, Jonathan Cirtain, I. De Moortel, Paola Testa, G. D. R. Attrill, Pietro N. Bernasconi, A. R. Davey, Justin C. Kasper, R. T. J. McAteer, Petrus C. Martens, Véronique Delouille, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Department of Physics [Bozeman], Montana State University (MSU), Department of Astronomy [Boston], Boston University [Boston] (BU), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Royal Observatory of Belgium [Brussels] (ROB), HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), NASA Marshall Space Flight Center (MSFC), Southwest Research Institute [Boulder] (SwRI), Department of Computer Science [Bozeman], School of Mathematics and Statistics [St Andrews], University of St Andrews [Scotland], Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Research Center for Astronomy and Applied Mathematics [Athens], Academy of Athens, Trinity College Dublin, Lockheed Martin Advanced Technology Center (ATC), Smithsonian Institution-Harvard University [Cambridge], and Max-Planck-Institut für Sonnensystemforschung (MPS)
Subjects: 010504 meteorology & atmospheric sciences, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Coronal hole, 01 natural sciences, Software, Heliophysics, Observatory, 0103 physical sciences, Coronal mass ejection, Astrophysics::Solar and Stellar Astrophysics, Computer vision, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Sunspot, Solar observatory, business.industry, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy, Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 13. Climate action, Space and Planetary Science, Physics::Space Physics, Large Angle and Spectrometric Coronagraph, Artificial intelligence, business
Abstract: International audience; In Fall 2008 NASA selected a large international consortium to produce a comprehensive automated feature-recognition system for the Solar Dynamics Observatory (SDO). The SDO data that we consider are all of the Atmospheric Imaging Assembly (AIA) images plus surface magnetic-field images from the Helioseismic and Magnetic Imager (HMI). We produce robust, very efficient, professionally coded software modules that can keep up with the SDO data stream and detect, trace, and analyze numerous phenomena, including flares, sigmoids, filaments, coronal dimmings, polarity inversion lines, sunspots, X-ray bright points, active regions, coronal holes, EIT waves, coronal mass ejections (CMEs), coronal oscillations, and jets. We also track the emergence and evolution of magnetic elements down to the smallest detectable features and will provide at least four full-disk, nonlinear, force-free magnetic field extrapolations per day. The detection of CMEs and filaments is accomplished with Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph (LASCO) and ground-based Hα data, respectively. A completely new software element is a trainable feature-detection module based on a generalized image-classification algorithm. Such a trainable module can be used to find features that have not yet been discovered (as, for example, sigmoids were in the pre-Yohkoh era). Our codes will produce entries in the Heliophysics Events Knowledgebase (HEK) as well as produce complete catalogs for results that are too numerous for inclusion in the HEK, such as the X-ray bright-point metadata. This will permit users to locate data on individual events as well as carry out statistical studies on large numbers of events, using the interface provided by the Virtual Solar Observatory. The operations concept for our computer vision system is that the data will be analyzed in near real time as soon as they arrive at the SDO Joint Science Operations Center and have undergone basic processing. This will allow the system to produce timely space-weather alerts and to guide the selection and production of quicklook images and movies, in addition to its prime mission of enabling solar science. We briefly describe the complex and unique data-processing pipeline, consisting of the hardware and control software required to handle the SDO data stream and accommodate the computer-vision modules, which has been set up at the Lockheed-Martin Space Astrophysics Laboratory (LMSAL), with an identical copy at the Smithsonian Astrophysical Observatory (SAO).
Published: 2012
Full Text: View/download PDF

15. In situ mass spectrometry during the Lutetia flyby

Author: S. A. Fuselier, Henri Rème, Myrtha Hässig, Peter Wurz, J. De Keyser, Annette Jäckel, L. Hofer, B. Fiethe, B. Schläppi, Jean-Jacques Berthelier, Kathrin Altwegg, Ursina Calmonte, Urs Mall, Martin Rubin, Hans Balsiger, Physikalisches Institut [Bern], Universität Bern [Bern], HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Institute of Computer and Network Engineering [Braunschweig] (IDA), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), University of Michigan [Ann Arbor], University of Michigan System, Universität Bern [Bern] (UNIBE), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: In situ, [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], 010504 meteorology & atmospheric sciences, Spacecraft outgassing, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], ROSINA, Mass spectrometry, 01 natural sciences, Astrobiology, 0103 physical sciences, Rosetta, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Spacecraft, business.industry, Astronomy, Astronomy and Astrophysics, Lutetia, in situ mass spectrometry, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Outgassing, 13. Climate action, Space and Planetary Science, Asteroid, Aspect angle, business, Exosphere
Abstract: International audience; During the Rosetta flyby at asteroid Lutetia the ROSINA instrument tried to detect a thin exosphere of the asteroid. Although the instrument is sensitive enough to detect even very tenuous gases at a density level of 1 cm−3 the Lutetia exosphere could not be unambiguously detected due to spacecraft outgassing, which was not constant because of the changing solar aspect angle. An upper limit for a water exosphere density at the flyby distance of 3160 km of (3.5±1.0)*103 cm−3 was deduced from the measurements.
Published: 2012
Full Text: View/download PDF

16. Influence of spacecraft outgassing on the exploration of tenuous atmospheres with in situ mass spectrometry

Author: Schlappi, Bernhard, Altwegg, Kathrin, Balsiger, Hans, Hassig, Myrtha, Jackel, A., Wurz, P., Fiethe, B., Rubin, Martin, Fuselier, S. A., Berthelier, Jean-Jacques, de Keyser, J., Reme, H., Mall, U., Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Institute of Computer and Network Engineering [Braunschweig] (IDA), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], University of Michigan [Ann Arbor], University of Michigan System, Lockheed Martin Advanced Technology Center (ATC), HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Universität Bern [Bern], Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, and Max-Planck-Institut für Sonnensystemforschung (MPS)
Subjects: Atmosphere/exosphere, Mass spectrometry, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Outgassing, 520 Astronomy, Physics::Space Physics, interference, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics::Earth and Planetary Astrophysics, 620 Engineering
Abstract: International audience; In situ mass spectrometry has been a powerful tool in many space missions to investigate atmospheres and exospheres of different bodies in the solar system. Applying new technologies, the mass spectrometers have become increasingly more sensitive. In this study, we show that spacecraft outgassing, which can never be completely prevented, will be the limiting factor in future missions that investigate very tenuous atmospheres and exospheres of moons, asteroids, or comets at large heliocentric distances. The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument on the European Space Agency Rosetta mission has monitored spacecraft outgassing for 6 years during the cruise phase with unprecedented instrument sensitivity. It is shown that diffusion of gas from materials and from the spacecraft interior plays an important role in maintaining a relatively permanent thin gas cloud around the spacecraft for many years. The density and composition of this gas cloud depends on location on the spacecraft, maneuvers, and payload activity. The main contaminants are water, which is adsorbed on cold surfaces, and organics from the spacecraft structure, electronics, and insulations. Decomposed lubricant material can give a significant contribution to the total background. Fortunately for Rosetta, outgassing of the spacecraft will play a minor role when the comet is close to perihelion; only in the early phase of the mission the outgassing may be larger than the cometary signature
Published: 2010
Full Text: View/download PDF

17. What ion energy steps observed by Cluster in the polar cusp can tell us about reconnection at the magnetopause?

Author: Escoubet, P., Taylor, M. G., Berchem, J., Bosqued, Jean-Michel, Trattner, K. J., Pitout, Frederic, Laakso, H., Masson, Arnaud, Dunlop, M.W., Dandouras, I., Reme, H., Fazakerley, A. N., European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Laboratoire de Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), and University College of London [London] (UCL)
Subjects: Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics
Abstract: SM51A-06; The polar cusps are two regions of the magnetosphere where the influence of the interplanetary magnetic field (IMF) is particularly strong. When the IMF is southward the plasma enters the cusp around the subsolar point or near the equatorward boundary of the cusp and on the other hand when the IMF is northward, the plasma enters through the lobes or the poleward boundary of the cusp. Subsequently the ions precipitating in the cusp are dispersed poleward when the IMF is southward and equatorward when the IMF is northward. This dispersion is caused by the motion of field lines driven by the magnetic tension away from the reconnection point. If reconnection is continuous and operates at constant rate, the ion dispersion is smooth and continuous. On the other hand if the reconnection rate varies, we expect interruption in the dispersion forming energy steps or staircase. On 23 September 2004 as the 4 Cluster spacecraft were crossing the mid-altitude polar cusp within 2- 16 minute from each other. The first two spacecraft, separated by about 1min 20s observed a typical Bz-South ion dispersion, where the energy of the ions decreases as latitude increases. The dispersion was not smooth but presented discontinuities that were the same on the two spacecraft. We will compare these dispersions and investigate the possible causes of their similarity. Other examples of cusp crossings with different time delay between the spacecraft will be analysed to investigate the origin of the discontinuities.
Published: 2008

18. Effect of a northward turning of the interplanetary magnetic field on cusp precipitation as observed by Cluster

Author: Escoubet, P., Berchem, J., Bosqued, Jean-Michel, Trattner, K. J., Taylor, M. G., Pitout, Frederic, Laakso, H., Masson, Arnaud, Dunlop, M.W., Dandouras, I., Reme, H., Fazakerley, A. N., Daly, P., European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Laboratoire de Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), University College of London [London] (UCL), Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Agence Spatiale Européenne = European Space Agency (ESA), University of California (UC)-University of California (UC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)
Subjects: POLAR CUSP, MAGNETOSHEATH PLASMA, CONVECTION, [SDU]Sciences of the Universe [physics], MAGNETOSPHERE, Physics::Space Physics, RECONNECTION, MAGNETOPAUSE, LATITUDE, GROUND-BASED OBSERVATIONS, LOW-ALTITUDE OBSERVATIONS, IMF, Astrophysics::Galaxy Astrophysics
Abstract: International audience; The immediate effect of the rotation of the interplanetary magnetic field (IMF) from southward to northward on cusp precipitation has been rarely observed by a polar orbiting satellite in the past. The four Cluster spacecraft observed such an event on 23 September 2004 as they were crossing the polar cusp within 2–16 min from each other. Between the first three and the last spacecraft crossing the cusp, the IMF rotated from southward to northward with a dominant By (GSM) component. For the first time we can examine the changes in the particle precipitation immediately after such IMF change. The first two spacecraft observed typical IMF-southward ion dispersion, while the last one observed both an IMF-southward-like dispersion in the boundary layer and an IMF-northward dispersion in the cusp. After the IMF turning, the cusp is shown to have grown in size in both the poleward and equatorward directions. A three-dimensional magnetohydrodynamic simulation is used to determine the locations of the sources of the ions and the topology of the magnetic field during the event.
Published: 2008
Full Text: View/download PDF

19. Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI)

Author: O. C. St. Cyr, Jeffrey S. Newmark, S. Cooper, T. Carter, C. J. Eyles, W. Deutsch, Simon Plunkett, James R. Lemen, E. Mentzell, Franck Delmotte, J. W. Cook, Christopher J. Davis, Richard A. Harrison, Dennis G. Socker, Joseph M. Davila, Kimberly I. Mehalick, Volker Bothmer, A. Moore, Jean-Pierre Wuelser, Russell A. Howard, V. Stephens, Marie-Françoise Ravet, R. Baugh, Jean-Philippe Halain, H. Mapson-Menard, N. Rich, Nicholas R. Waltham, C. J. Wolfson, A. Hurley, Dexter W. Duncan, Jean-Pierre Delaboudiniere, F. Auchère, Clarence M. Korendyke, William T. Thompson, Jean-Marc Defise, Emmanuel Mazy, G. Maahs, Pierre Rochus, Raymond Mercier, G. M. Simnett, J. Lang, D. R. McMullin, John D. Moses, T. D. Tarbell, Angelos Vourlidas, Dennis Wang, E. O. Hulburt Center for Space Research, Naval Research Laboratory (NRL), NASA Goddard Space Flight Center (GSFC), Lockheed Martin Solar and Astrophysics laboratory (LMSAL), Lockheed Martin Advanced Technology Center (ATC), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Astrophysics and Space Research group [Birmingham], University of Birmingham [Birmingham], Centre Spatial de Liège (CSL), Université de Liège, Laboratoire Charles Fabry de l'Institut d'Optique / Scop, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11), Institut d'astrophysique spatiale (IAS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Sud - Paris 11 (UP11), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Interferometrics, Inc, HYTEC Inc., PRAXIS Inc., PRAXIS Inc, and Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Solar System, 010504 meteorology & atmospheric sciences, 7. Clean energy, 01 natural sciences, law.invention, Telescope, Observatory, law, 0103 physical sciences, Coronal mass ejection, 14. Life underwater, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Remote sensing, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Spacecraft, business.industry, Astronomy, Astronomy and Astrophysics, Coronal loop, Space and Planetary Science, Large Angle and Spectrometric Coronagraph, business, Heliosphere
Abstract: The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) is a five telescope package, which has been developed for the Solar Terrestrial Relation Observatory (STEREO) mission by the Naval Research Laboratory (USA), the Lockheed Solar and Astrophysics Laboratory (USA), the Goddard Space Flight Center (USA), the University of Birmingham (UK), the Rutherford Appleton Laboratory (UK), the Max Planck Institute for Solar System Research (Germany), the Centre Spatiale de Leige (Belgium), the Institut d’Optique (France) and the Institut d’Astrophysique Spatiale (France). SECCHI comprises five telescopes, which together image the solar corona from the solar disk to beyond 1 AU. These telescopes are: an extreme ultraviolet imager (EUVI: 1–1.7 R⊙), two traditional Lyot coronagraphs (COR1: 1.5–4 R⊙ and COR2: 2.5–15 R⊙) and two new designs of heliospheric imagers (HI-1: 15–84 R⊙ and HI-2: 66–318 R⊙). All the instruments use 2048×2048 pixel CCD arrays in a backside-in mode. The EUVI backside surface has been specially processed for EUV sensitivity, while the others have an anti-reflection coating applied. A multi-tasking operating system, running on a PowerPC CPU, receives commands from the spacecraft, controls the instrument operations, acquires the images and compresses them for downlink through the main science channel (at compression factors typically up to 20×) and also through a low bandwidth channel to be used for space weather forecasting (at compression factors up to 200×). An image compression factor of about 10× enable the collection of images at the rate of about one every 2–3 minutes. Identical instruments, except for different sizes of occulters, are included on the STEREO-A and STEREO-B spacecraft.
Published: 2008

20. Cusp particle precipitation before and after an abrupt change of direction of the IMF

Author: Escoubet, P., Berchem, J., Bosqued, Jean-Michel, Taylor, M. G., Trattner, K. J., Pitout, Frederic, Laakso, H., Masson, Arnaud, Dunlop, M.W., Dandouras, I., Reme, H., Fazakerley, A. N., Daly, P., European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Laboratoire de Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), University College of London [London] (UCL), Max Planck Institute for Solar System Research (MPS), and Max-Planck-Gesellschaft
Subjects: Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics, Physics::Geophysics
Abstract: SM22B-05; The polar cusp is a highly dynamic region responding very quickly to changes in the Interplanetary Magnetic Field (IMF) direction and solar wind dynamic pressure. The immediate effect of the rotation of the Interplanetary Magnetic Field (IMF) from southward to northward on cusp precipitation has been rarely observed by a polar orbiting satellite in the past. The four Cluster spacecraft observed such an event on 23 September 2004 as they were crossing the polar cusp within 2-16 minute from each other. Between the first three and the last spacecraft crossing the cusp, the IMF rotated from southward to northward with a dominant By (GSM) component. For the first time we can examine the changes in the particle precipitation immediately after such IMF change. The first two spacecraft observed a typical IMF-southward ion dispersion, while the last one observed both an IMF- Southward-like dispersion in the boundary layer and an IMF-northward dispersion in the cusp. After the IMF turning, the cusp is shown to have grown in size in both the poleward and equatorward directions. A three- dimensional magnetohydrodynamic (MHD) simulation is used to determine the locations of the sources of the ions and the topology of the magnetic field during the event. After the turning of the IMF northward, the simulation shows first a reconnection on the dawn northern lobes, poleward of the cusp, and then a second reconnection of the same field line on the dusk lobe in the southern hemisphere. We would then have a case of double lobe reconnection when the IMF is northward with a dominant By component (clock angle between 45 and 60 deg.).
Published: 2007

21. Two sources of magnetosheath ions observed by Cluster in the mid-altitude polar cusp

Author: Escoubet, P., Berchem, J., Bosqued, Jean-Michel, Trattner, K. J., Taylor, M. G., Pitout, Frederic, Laakso, H., Masson, Arnaud, Dunlop, M.W., Reme, H., Dandouras, I., Fazakerley, A. N., European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Extraterrestrische Physik (MPE), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), and University College of London [London] (UCL)
Published: 2006

22. Onset of reconnection observed by Cluster in the mid-altitude polar cusp

Author: Escoubet, P., Berchem, J., Bosqued, Jean-Michel, Trattner, K. J., Taylor, M. G., Pitout, Frederic, Laakso, H., Masson, Arnaud, Dunlop, M.W., Reme, H., Dandouras, I., Fazakerley, A. N., European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Extraterrestrische Physik (MPE), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), and University College of London [London] (UCL)
Published: 2006

23. Cluster observations of two sources of magnetosheath ions in the mid-altitude polar cusp

Author: Escoubet, P., Berchem, J., Bosqued, Jean-Michel, Trattner, K. J., Taylor, M. G., Pitout, Frederic, Vallat, C., Laakso, H., Masson, Arnaud, Dunlop, M.W., Reme, H., Dandouras, I., Fazakerley, A. N., European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Extraterrestrische Physik (MPE), Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), and University College of London [London] (UCL)
Subjects: Physics::Space Physics
Abstract: SM53A-1429; Double cusps have been observed on a few occasions by polar orbiting spacecraft and ground-based observatories. On 7 Aug. 2004, Cluster 4 was moving poleward through the Northern cusp, followed by Cluster 1, Cluster 2, and finally Cluster 3. The Wind spacecraft detected a Southward turning of the Interplanetary Magnetic Field (IMF) at the beginning of the cusp crossings and IMF-Bz stayed negative throughout. Cluster 4 observed a high energy step in the ion dispersion around 1 keV on the equatorward side of the cusp. Cluster 1, entering the cusp around 1 minute later, did not observe the high energy step anymore but a partial dispersion with a low energy cut-off reaching 100 eV. About 9 minutes later, Cluster 3 entered the cusp and observed full ion dispersion from a few keV down to around 50 eV. All spacecraft observed a less structured and strong ion precipitation region in the centre of the cusp. The flow deduced from the ion distributions was directed poleward and Eastward in the step/dispersion, whereas in the centre of the cusp, the ion and electron fluxes were higher and the flow was directed mainly westward. This event could be explained by the onset of dayside reconnection when the IMF turned southward. The step would be the first signature of component reconnection, and the injection in the centre of the cusp be produced by anti-parallel reconnection in the northern dusk flank. A three-dimensional magnetohydrodynamic (MHD) simulation is used to help us to locate the sources of the ions and the topology of the magnetic field during the event.
Published: 2006

24. Temporal evolution of a staircase ion signature observed by Cluster in the mid-altitude polar cusp

Author: Jean Berchem, Andrew Fazakerley, Karlheinz Trattner, Frederic Pitout, J. M. Bosqued, Arnaud Masson, H. Rème, C. P. Escoubet, H. E. Laakso, Iannis Dandouras, Matthew Taylor, Malcolm Dunlop, European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, Lockheed Martin Advanced Technology Center (ATC), Max-Planck-Institut für Extraterrestrische Physik (MPE), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), Mullard Space Science Laboratory (MSSL), University College of London [London] (UCL), Agence Spatiale Européenne = European Space Agency (ESA), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and University of California (UC)-University of California (UC)
Subjects: 010504 meteorology & atmospheric sciences, INTERPLANETARY MAGNETIC-FIELD, Magnetosphere, Electron precipitation, Astrophysics, 01 natural sciences, Ion, FLUX-TRANSFER EVENTS, MAGNETOPAUSE RECONNECTION, 0103 physical sciences, Cluster (physics), Interplanetary magnetic field, Dispersion (water waves), LOW-ALTITUDE OBSERVATIONS, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Cusp (singularity), Geophysics, 13. Climate action, EDGE, [SDU]Sciences of the Universe [physics], PRECIPITATION, Physics::Space Physics, General Earth and Planetary Sciences, Polar, AURORA
Abstract: International audience; We use the Cluster string of pearls configuration to investigate temporal variations of ion precipitation in the mid-altitude polar cusp. On 7 Aug. 2004, Cluster 4 was moving poleward through the Northern cusp, followed by Cluster 1, Cluster 2, and finally Cluster 3. The Wind spacecraft detected a Southward turning of the Interplanetary Magnetic Field (IMF) at the beginning of the cusp crossings and IMF-Bz stayed negative throughout. Cluster 4 observed a high energy step in the ion dispersion around 1 keV on the equatorward side of the cusp. C1, entering the cusp around 1 minute later, did not observe the high energy step anymore but a partial dispersion with a low energy cut-off reaching 100 eV. About 9 min later, C3 entered the cusp and observed a full ion dispersion from a few keV down to around 50 eV. The open-closed boundary, identified by electron precipitation, was initially moving equatorward at a rate of −0.43° ILAT/minute at the beginning of the event and then slowed down to −0.16° ILAT/minute, suggesting the erosion of the dayside magnetosphere under IMF Southward. This event is explained by the onset of dayside reconnection when the IMF turned southward; the step being the first signature of the reconnection that would then evolve as a full dispersion as reconnection goes on. We observed 1–3 keV ions near the open-closed boundary on the three spacecraft crossings that suggests a continuous reconnection during about 9 minutes.
Published: 2006
Full Text: View/download PDF

25. VITRUV - Science Cases

Author: Garcia, Paulo J. V., Jean-Phillipe Berger, Romano Corradi, Thierry Forveille, Tim Harries, Gilles Henri, Fabien Malbet, Alessandro Marconi, Karine Perraut, Pierre-Olivier Petrucci, Karel Schrijver, Leonardo Testi, Éric Thiébaut, Sebastian Wolf, Centro de Astrofísica da Universidade do Porto (CAUP), Universidade do Porto, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Isaac Newton Group of Telescopes (ING), Instituto de Astrofisica de Canarias (IAC), Canada-France-Hawaii Telescope Corporation (CFHT), National Research Council of Canada (NRC)-Centre National de la Recherche Scientifique (CNRS)-University of Hawai'i [Honolulu] (UH), School of Physics (EXETER), University of Exeter, INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Lockheed Martin Solar and Astrophysics Laboratory (LMSAL), Lockheed Martin Advanced Technology Center (ATC), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, The European Southern Observatory (ESO), F. Paresce, A. Richichi, A. Chelli et al., Universidade do Porto = University of Porto, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Optical Interferometry, Very Large Telescopes, Visible, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Infrared, Instrumentation, Compact objects, Spectro-Imaging, Astrophysics::Galaxy Astrophysics
Abstract: VITRUV is a second generation spectro-imager for the PRIMA enabled Very Large Telescope Interferometer. By combining simultaneously up to 8 telescopes VITRUV makes the VLTI up to 6 times more efficient. This operational gain allows two novel scientific methodologies: 1) massive surveys of sizes; 2) routine interferometric imaging. The science cases presented concentrate on the qualitatively new routine interferometric imaging methodology. The science cases are not exhaustive but complementary to the PRIMA reference mission. The focus is on: a) the close environment of young stars probing for the initial conditions of planet formation and disk evolution; b) the surfaces of stars tackling dynamos, activity, pulsation, mass-loss and evolution; c) revealing the origin of the extraordinary morphologies of Planetary Nebulae and related stars; d) studying the accretion-ejection structures of stellar black-holes (microquasars) in our galaxy; e) unveiling the different interacting components (torus, jets, BLRs) of Active Galactic Nuclei; and f) probing the environment of nearby supermassive black-holes and relativistic effects in the Galactic Center black-hole., 15 pages. The Power of Optical/IR Interferometry: Recent Scientific Results and 2nd Generation VLTI Instrumentation, Allemagne (2005) in press
Published: 2005

26. Coordinated polar spacecraft, geosynchronous spacecraft, and ground-based observations of magnetopause processes and their coupling to the ionosphere

Author: Chao-Song Huang, T. E. Moore, Christopher T. Russell, K. Yumoto, Y. Zheng, S.-H. Chen, S. M. Petrinec, James A. Slavin, Guan Le, Howard J. Singer, John C. Samson, GSFC Laboratory for Extraterrestrial Physics, NASA Goddard Space Flight Center (GSFC), Universities Space Research Association (USRA), Institute of Geophysics and Planetary Physics [Los Angeles] (IGPP), University of California [Los Angeles] (UCLA), University of California-University of California, MIT Haystack Observatory, Massachusetts Institute of Technology (MIT), Space Physics Laboratory, Lockheed Martin Advanced Technology Center (ATC), Department of Physics [Edmonton], University of Alberta, NOAA Space Environment Center, National Oceanic and Atmospheric Administration (NOAA), Space Environment Research Center [Kyushu] (SERC), and Kyushu University [Fukuoka]
Subjects: Atmospheric Science, 010504 meteorology & atmospheric sciences, Field line, Magnetosphere, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 01 natural sciences, Current sheet, Magnetosheath, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), lcsh:Science, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, lcsh:QC801-809, Geology, Astronomy and Astrophysics, Geophysics, lcsh:QC1-999, Solar wind, lcsh:Geophysics. Cosmic physics, Polar wind, 13. Climate action, Space and Planetary Science, Physics::Space Physics, Magnetopause, lcsh:Q, Magnetohydrodynamics, lcsh:Physics
Abstract: In this paper, we present in-situ observations of processes occurring at the magnetopause and vicinity, including surface waves, oscillatory magnetospheric field lines, and flux transfer events, and coordinated observations at geosynchronous orbit by the GOES spacecraft, and on the ground by CANOPUS and 210° Magnetic Meridian (210MM) magnetometer arrays. On 7 February 2002, during a high-speed solar wind stream, the Polar spacecraft was skimming the magnetopause in a post-noon meridian plane for ~3h. During this interval, it made two short excursions and a few partial crossings into the magnetosheath and observed quasi-periodic cold ion bursts in the region adjacent to the magnetopause current layer. The multiple magnetopause crossings, as well as the velocity of the cold ion bursts, indicate that the magnetopause was oscillating with an ~6-min period. Simultaneous observations of Pc5 waves at geosynchronous orbit by the GOES spacecraft and on the ground by the CANOPUS magnetometer array reveal that these magnetospheric pulsations were forced oscillations of magnetic field lines directly driven by the magnetopause oscillations. The magnetospheric pulsations occurred only in a limited longitudinal region in the post-noon dayside sector, and were not a global phenomenon, as one would expect for global field line resonance. Thus, the magnetopause oscillations at the source were also limited to a localized region spanning ~4h in local time. These observations suggest that it is unlikely that the Kelvin-Helmholz instability and/or fluctuations in the solar wind dynamic pressure were the direct driving mechanisms for the observed boundary oscillations. Instead, the likely mechanism for the localized boundary oscillations was pulsed reconnection at the magnetopause occurring along the X-line extending over the same 4-h region. The Pc5 band pressure fluctuations commonly seen in high-speed solar wind streams may modulate the reconnection rate as an indirect cause of the observed Pc5 pulsations. During the same interval, two flux transfer events were also observed in the magnetosphere near the oscillating magnetopause. Their ground signatures were identified in the CANOPUS data. The time delays of the FTE signatures from the Polar spacecraft to the ground stations enable us to estimate that the longitudinal extent of the reconnection X-line at the magnetopause was ~43° or ~5.2 RE. The coordinated in-situ and ground-based observations suggest that FTEs are produced by transient reconnection taking place along a single extended X-line at the magnetopause, as suggested in the models by Scholer(1988) and Southwood et al.(1988). The observations from this study suggest that the reconnection occurred in two different forms simultaneously in the same general region at the dayside magnetopause: 1) continuous reconnection with a pulsed reconnection rate, and 2) transient reconnection as flux transfer events. Key words. Magnetospheric physics (Magnetopause, cusp and boundary layers; Magnetosphere-ionosphere interactions; MHD waves and instabilities)
Published: 2004

27. Rosina’s Scientific Perspective at Comet Churyumov-Gerasimenko

Author: Tamas I. Gombosi, Fritz Gliem, Jean-Jacques Berthelier, H. Rème, Kathrin Altwegg, E. Arijs, Hans Balsiger, Annette Jäckel, A. Korth, S. A. Fuselier, Physikalisches Institut [Bern], Universität Bern [Bern], Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lockheed Martin Advanced Technology Center (ATC), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Space Physics Research Laboratory [Ann Arbor] (SPRL), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Max-Planck-Institut für Aeronomie (MPI Aeronomie), Max-Planck-Gesellschaft, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Colangeli L., Epifani E.M., and Palumbo P. (eds)
Subjects: Physics, Molecular composition, 010504 meteorology & atmospheric sciences, Comet, Astronomy, 01 natural sciences, law.invention, Astrobiology, On board, Orbiter, law, [SDU]Sciences of the Universe [physics], 0103 physical sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: International audience; The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on board Rosetta is designed to analyze the volatile material of comet 67P/Churyumov-Gerasimenko. We show in this paper that the scientific requirements related to the volatile material of comets in general and specifically to the present Rosetta target can be met by the three ROSINA sensors. ROSINA will answer scientifically important questions concerning the elemental, isotopic and molecular composition of Churyumov-Gerasimenko.
Published: 2004

28. Stratosphere over Dumont d'Urville, Antarctica, in winter 1992

Author: J. L. Mergenthaler, Sophie Godin, Jean-Pierre Pommereau, Florence Goutail, E. Monnier, Lucien Froidevaux, Martyn P. Chipperfield, Joe W. Waters, Christine David, Philippe Ricaud, Aidan E. Roche, Hugh C. Pumphrey, Observatoire Bordeaux, Université Sciences et Technologies - Bordeaux 1, Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Lockheed Martin Advanced Technology Center (ATC), School of Geosciences [Edinburgh], University of Edinburgh, Department of Chemistry [Cambridge, UK], University of Cambridge [UK] (CAM), Université Sciences et Technologies - Bordeaux 1 (UB), and NASA-California Institute of Technology (CALTECH)
Subjects: Atmospheric Science, 010504 meteorology & atmospheric sciences, Chemical transport model, Total Ozone Mapping Spectrometer, Soil Science, Aquatic Science, 010502 geochemistry & geophysics, Oceanography, Atmospheric sciences, 01 natural sciences, Atmosphere, chemistry.chemical_compound, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), Stratosphere, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Ecology, Chlorine nitrate, Paleontology, Forestry, Vortex, Microwave Limb Sounder, Geophysics, chemistry, 13. Climate action, Space and Planetary Science, Environmental science, Chlorine monoxide
Abstract: International audience; We present an analysis of the temporal evolution of stratospheric constituents above the station of Dumont d'Urville in Antarctica (67°S, 140°E) from August 14 to September 20, 1992. Data sets include temperature profiles and H2O, ClO, O3, NO2, ClONO2, HNO3, N2O, and CH4 mixing ratios and aerosol extinction coefficients from 46 to 1 hPa measured by the Microwave Limb Sounder (MLS) and the Cryogenic Limb Array Etalon Spectrometer (CLAES) instruments aboard the Upper Atmosphere Research Satellite (UARS). At the station, aerosol extinction coefficients and O3 profiles are obtained by a lidar together with O3 profiles provided by sondes. Integrated O3 and NO2 column amounts are given by a Système d'Analyse par Observation Zénithale (SAOZ) spectrometer located at the station. Column O3 is also provided by the Total Ozone Mapping Spectrometer (TOMS) instrument aboard the NIMBUS 7 satellite, complemented with potential vorticity derived from the U.K. Meteorological Office assimilated data set and temperature fields provided by the European Centre for Medium-Range Weather Forecasts. Time evolution of these measurements is interpreted by comparison with results from the SLIMCAT three-dimensional chemical transport model. We show that the site is near the vortex edge on average and is alternately inside the vortex or just outside in the region referred to as the "collar" region. There are no observations of polar stratospheric clouds (PSCs) over the station above 46 hPa (∼18 km). In fact, PSCs mainly appear over the Palmer Peninsula area at 46 hPa. The rates of change of chemical species are evaluated at 46 hPa when the station is conservatively inside the vortex collar region. The ozone loss rate is 0.04 ppmv d-1 (∼1.3% d-1), which is consistent with other analyses of southern vortex ozone loss rates; chlorine monoxide tends to decrease by 0.03 ppbv d-1, while chlorine nitrate increases by 0.025 ppbv d-1. These negative ClO and positive ClONO2 trends are only observed in the collar region of the vortex where O3 amounts are far from near zero, and little denitrification is observed. Loss and production rates as measured by UARS are more pronounced than the ones deduced from the SLIMCAT model, probably because of the moderate model horizontal resolution (3.75° × 3.75°), which is not high enough to resolve the vortex crossings above Dumont d'Urville and which leads to a larger extent of denitrified air than indicated by the UARS data. The analysis also shows activated ClO inside the vortex at 46 hPa, a dehydrated vortex at 46 hPa, and rehydrated above, with no trace of denitrification in the lower stratosphere. Good agreement between coincident measurements of O3 profiles by UARS/MLS, lidar, and sondes is also observed. Finally, the agreement between UARS and SLIMCAT data sets is much better in the middle stratosphere (4.6 hPa) than in the lower stratosphere (46 hPa).
Published: 1998
Full Text: View/download PDF

29. Rosetta Orbiter Spectrometer for Ion and Neutral Analysis—ROSINA

Author: B. Wilken, E. Kopp, Stefano Livi, E. G. Shelley, D. T. Young, J. H. Waite, Lennard A. Fisk, Fritz Gliem, Hermann Wollnik, Peter Wurz, Tamas I. Gombosi, Joachim Woch, G. R. Carignan, Stephen A. Fuselier, H. Rème, A. G. Ghielmetti, J. L. Bertaux, E. Arijs, A. Korth, Hans Balsiger, Jean-Jacques Berthelier, Kathrin Altwegg, Christian Mazelle, J. A. Sauvaud, Peter Bochsler, Peter Eberhardt, Physikalisches Institut [Bern], Universität Bern [Bern], Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Space Physics Research Laboratory [Ann Arbor] (SPRL), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Lockheed Martin Advanced Technology Center (ATC), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Max-Planck-Institut für Aeronomie (MPI Aeronomie), Max-Planck-Gesellschaft, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Lockheed Martin Palo Alto Research Laboratories, Lockheed Martin Corporation, Space Science Division [San Antonio], Southwest Research Institute [San Antonio] (SwRI), Physikalisches Institut [Gießen], Justus-Liebig-Universität Gießen (JLU), Universität Bern [Bern] (UNIBE), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Justus-Liebig-Universität Gießen = Justus Liebig University (JLU)
Subjects: Physics, Atmospheric Science, Ion flow, 010504 meteorology & atmospheric sciences, Resolution (mass spectrometry), Spectrometer, Aerospace Engineering, Astronomy and Astrophysics, 7. Clean energy, 01 natural sciences, law.invention, Astrobiology, Ion, Orbiter, Geophysics, 13. Climate action, Space and Planetary Science, law, [SDU]Sciences of the Universe [physics], 0103 physical sciences, Wide dynamic range, High mass, General Earth and Planetary Sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: International audience; The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) will answer outstanding questions concerning the main objectives of the mission. To accomplish the very demanding objectives, ROSINA will have unprecedented capabilities, including: very wide mass range from 1 amu to >300 amu; very high mass resolution (ability to resolve CO from N2 and 13C from 12CH); very wide dynamic range and high sensitivity; the ability to determine cometary gas and ion flow velocities and temperatures.
Published: 1998
Full Text: View/download PDF

30. Accuracy and precision of cryogenic limb array etalon spectrometer (CLAES) temperature retrievals

Author: Michael R. Gross, Aidan E. Roche, David P. Edwards, John C. Gille, Ian S. McDermid, Upendra N. Singh, Alain Hauchecorne, Paul L. Bailey, Thomas J. McGee, Alvin J. Miller, Steven T. Massie, John B. Kumer, Lawrence V. Lyjak, John L. Mergenthaler, Phillip Keckhut, National Center for Atmospheric Research [Boulder] (NCAR), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Lockheed Martin Advanced Technology Center (ATC), Department of Geological Sciences [Gainesville] (UF|Geological), University of Florida [Gainesville] (UF), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, NASA Langley Research Center [Hampton] (LaRC), Scripps Institution of Oceanography (SIO - UC San Diego), and University of California (UC)-University of California (UC)
Subjects: Atmospheric Science, Accuracy and precision, 010504 meteorology & atmospheric sciences, Soil Science, Aquatic Science, 010502 geochemistry & geophysics, Oceanography, Atmospheric sciences, 01 natural sciences, law.invention, Mesosphere, Atmosphere, Geochemistry and Petrology, law, Earth and Planetary Sciences (miscellaneous), Stratosphere, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, Remote sensing, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Ecology, Spectrometer, Paleontology, Forestry, Wavelength, Geophysics, 13. Climate action, Space and Planetary Science, Radiosonde, Environmental science, Satellite
Abstract: International audience; The Cryogenic Limb Array Etalon Spectrometer (CLAES) measured emission from the 792 cm−1 Q branch of CO2, from which temperature distributions in the stratosphere and low mesosphere were derived. Here we briefly review the measurement technique, concentrating on aspects that affect the temperature determination. Comparison of many pairs of retrievals at the same location (near 32°N or 32°S) measured on sequential orbits (time separation of 96 min) shows a precision ranging from approximately 0.8 K at 68 mbar to about 3.5 K at 0.2 mbar, which agrees with simulations incorporating random noise and short‐period spacecraft motions. Comparisons of globally analyzed CLAES data with National Meteorological Center (NMC) and U.K. Meteorological Office (UKMO) analyses show general agreement, with CLAES tending to be cooler by about 2 K, except in the tropics and high‐latitude winter conditions. This is supported by comparisons with individual radiosondes and several lidars that indicate that the agreement is within 2 K throughout the profile (except for a narrow layer around 3 mbar). An error analysis also indicates that systematic errors should be roughly 2 K, independent of altitude. The systematic differences at low latitudes appear to be due to tropical waves, which have vertical wavelengths too short to be seen by the TIROS Operational Vertical Sounder (TOVS) instruments. There are no correlative rocketsondes or lidars to help resolve the reasons for the high‐latitude differences. Comparisons with other Upper Atmosphere Research Satellite (UARS) data should shed additional light on this question.
Published: 1996
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources

Refine your results

30 results on '"Lockheed Martin Advanced Technology Center (ATC)"'

1. ROSINA/DFMS and IES observations of 67P: Ion-neutral chemistry in the coma of a weakly outgassing comet

2. Ion chemistry in the coma of comet 67P near perihelion

3. Dual storage and release of molecular oxygen in comet 67P/Churyumov-Gerasimenko

4. Changes in granulation scales over the solar cycle seen with SDO/HMI and Hinode/SOT

5. On the Ubiquity of Magnetic Reconnection Inside Flux Transfer Event‐Like Structures at the Earth's Magnetopause

6. Mass Loading the Earth's Dayside Magnetopause Boundary Layer and Its Effect on Magnetic Reconnection

7. Comparison of neutral outgassing of comet 67P/Churyumov-Gerasimenko inbound and outbound beyond 3 AU from ROSINA/DFMS

8. Nonlobe Reconnection at the Earth's Magnetopause for Northward IMF

9. Solar Ultraviolet Bursts

10. Two sources of magnetosheath ions observed by Cluster in the mid-altitude polar cusp

11. Rosina – Rosetta Orbiter Spectrometer for Ion and Neutral Analysis

12. Solar Magnetic Field Reversals and the Role of Dynamo Families

13. How the inclination of Earth's orbit affects incoming solar irradiance

14. Computer Vision for The Solar Dynamics Observatory

15. In situ mass spectrometry during the Lutetia flyby

16. Influence of spacecraft outgassing on the exploration of tenuous atmospheres with in situ mass spectrometry

17. What ion energy steps observed by Cluster in the polar cusp can tell us about reconnection at the magnetopause?

18. Effect of a northward turning of the interplanetary magnetic field on cusp precipitation as observed by Cluster

19. Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI)

20. Cusp particle precipitation before and after an abrupt change of direction of the IMF

21. Two sources of magnetosheath ions observed by Cluster in the mid-altitude polar cusp

22. Onset of reconnection observed by Cluster in the mid-altitude polar cusp

23. Cluster observations of two sources of magnetosheath ions in the mid-altitude polar cusp

24. Temporal evolution of a staircase ion signature observed by Cluster in the mid-altitude polar cusp

25. VITRUV - Science Cases

26. Coordinated polar spacecraft, geosynchronous spacecraft, and ground-based observations of magnetopause processes and their coupling to the ionosphere

27. Rosina’s Scientific Perspective at Comet Churyumov-Gerasimenko

28. Stratosphere over Dumont d'Urville, Antarctica, in winter 1992

29. Rosetta Orbiter Spectrometer for Ion and Neutral Analysis—ROSINA

30. Accuracy and precision of cryogenic limb array etalon spectrometer (CLAES) temperature retrievals

Catalog

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Journal

Database

Publisher

30 results on '"Lockheed Martin Advanced Technology Center (ATC)"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources