Ionospheric total electron content of comet 67P/Churyumov-Gerasimenko
| Autor: | Zoltán Németh, Martin Rubin, Pierre Henri, Marina Galand, Nicolas Gilet, Rajkumar Hajra, L. Bucciantini, Bruce T. Tsurutani, Xavier Vallières |
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| Přispěvatelé: | 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)-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, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Indian Institute of Technology Indore (IITI), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Imperial College London, University of Bern, California Institute of Technology (CALTECH), Hungarian Wigner Research Centre for Physics, ANR-15-CE31-0009,SPECTRA,Sonder le Plasma dans l'Environnement d'une ComètE avec RosettA(2015), 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), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Science and Technology Facilities Council (STFC) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
010504 meteorology & atmospheric sciences
TEC media_common.quotation_subject Comet Astrophysics Astronomy & Astrophysics 01 natural sciences Asymmetry comets: individual: 67P Sun: activity 0201 Astronomical and Space Sciences 0103 physical sciences 010303 astronomy & astrophysics Southern Hemisphere 0105 earth and related environmental sciences media_common Churyumov-Gerasimenko Physics [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] 520 Astronomy comets: general Northern Hemisphere Astronomy and Astrophysics Plasma 620 Engineering Sun: UV radiation methods: data analysis 13. Climate action Space and Planetary Science Orders of magnitude (length) Ionosphere |
| Zdroj: | Astronomy and Astrophysics-A&A Astronomy and Astrophysics-A&A, EDP Sciences, 2020, 635, pp.A51. ⟨10.1051/0004-6361/201937022⟩ Hajra, Rajkumar; Henri, Pierre; Vallières, Xavier; Galand, Marina; Rubin, Martin; Tsurutani, Bruce T.; Gilet, Nicolas; Bucciantini, Luca; Nemeth, Zoltan (2020). Ionospheric total electron content of comet 67P/Churyumov-Gerasimenko. Astronomy and astrophysics, 635, A51. EDP Sciences 10.1051/0004-6361/201937022 A51 |
| ISSN: | 0004-6361 |
| DOI: | 10.1051/0004-6361/201937022⟩ |
| Popis: | We study the evolution of a cometary ionosphere, using approximately two years of plasma measurements by the Mutual Impedance Probe on board the Rosetta spacecraft monitoring comet 67P/Churyumov-Gerasimenko (67P) during August 2014–September 2016. The in situ plasma density measurements are utilized to estimate the altitude-integrated electron number density or cometary ionospheric total electron content (TEC) of 67P based on the assumption of radially expanding plasma. The TEC is shown to increase with decreasing heliocentric distance (rh) of the comet, reaching a peak value of ~(133 ± 84) × 109cm−2averaged around perihelion (rh< 1.5 au). At large heliocentric distances (rh> 2.5 au), the TEC decreases by ~2 orders of magnitude. For the same heliocentric distance, TEC values are found to be significantly larger during the post-perihelion periods compared to the pre-perihelion TEC values. This “ionospheric hysteresis effect” is more prominent in the southern hemisphere of the comet and at large heliocentric distances. A significant hemispheric asymmetry is observed during perihelion with approximately two times larger TEC values in the northern hemisphere compared to the southern hemisphere. The asymmetry is reversed and stronger during post-perihelion (rh> 1.5 au) periods with approximately three times larger TEC values in the southern hemisphere compared to the northern hemisphere. Hemispheric asymmetry was less prominent during the pre-perihelion intervals. The correlation of the cometary TEC with the incident solar ionizing fluxes is maximum around and slightly after perihelion (1.5 au |
| Databáze: | OpenAIRE |
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