HDO and SO2 thermal mapping on Venus

Autor: Encrenaz, Thérèse, Greathouse, Thomas K., Marcq, Emmanuel, Sagawa, H., Widemann, Thomas, Bézard, Bruno, Fouchet, Thierry, Lefèvre, Franck, Lebonnois, Sébastien, Atreya, S. K., Lee, Y. J., Giles, R., Watanabe, S., Shao, W., Zhang, Xi, Bierson, C. J.
Přispěvatelé: 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), Southwest Research Institute [San Antonio] (SwRI), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), 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), Kyoto Sangyo University, STRATO - LATMOS, Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Planetary Science Laboratory [Ann Arbor] (PSL), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Zentrum für Astronomie und Astrophysik [Berlin] (ZAA), Technical University of Berlin / Technische Universität Berlin (TU), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Hokkaido Information University, Department of Earth and Planetary Sciences [Santa Cruz], University of California [Santa Cruz] (UC Santa Cruz), University of California (UC)-University of California (UC), European Project: 606798,EC:FP7:SPA,FP7-SPACE-2013-1,EUROVENUS(2013), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), 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), 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), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Technische Universität Berlin (TU), University of California [Santa Cruz] (UCSC), University of California-University of California
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Astronomy and Astrophysics-A&A
Astronomy and Astrophysics-A&A, 2020, 639, pp.A69. ⟨10.1051/0004-6361/202037741⟩
Astronomy and Astrophysics-A&A, EDP Sciences, 2020, 639, pp.A69. ⟨10.1051/0004-6361/202037741⟩
ISSN: 0004-6361
DOI: 10.1051/0004-6361/202037741⟩
Popis: International audience Since January 2012, we have been monitoring the behavior of sulfur dioxide and water on Venus, using the Texas Echelon Cross-Echelle Spectrograph imaging spectrometer at the NASA InfraRed Telescope Facility (IRTF, Mauna Kea Observatory). Here, we present new data recorded in February and April 2019 in the 1345 cm−1 (7.4 μm) spectral range, where SO2, CO2, and HDO (used as a proxy for H2O) transitions were observed. The cloud top of Venus was probed at an altitude of about 64 km. As in our previous studies, the volume mixing ratio (vmr) of SO2 was estimated using the SO2/CO2 line depth ratio of weak transitions; the H2O volume mixing ratio was derived from the HDO/CO2 line depth ratio, assuming a D/H ratio of 200 times the Vienna standard mean ocean water. As reported in our previous analyses, the SO2 mixing ratio shows strong variations with time and also over the disk, showing evidence for the formation of SO2 plumes with a lifetime of a few hours; in contrast, the H2O abundance is remarkably uniform over the disk and shows moderate variations as a function of time. We have used the 2019 data in addition to our previous dataset to study the long-term variations of SO2 and H2O. The data reveal a long-term anti-correlation with a correlation coefficient of −0.80; this coefficient becomes −0.90 if the analysis is restricted to the 2014–2019 time period. The statistical analysis of the SO2 plumes as a function of local time confirms our previous result with a minimum around 10:00 and two maxima near the terminators. The dependence of the SO2 vmr with respect to local time shows a higher abundance at the evening terminator with respect to the morning. The dependence of the SO2 vmr with respect to longitude exhibits a broad maximum at 120–200° east longitudes, near the region of Aphrodite Terra. However, this trend has not been observed by other measurements and has yet to be confirmed.
Databáze: OpenAIRE
Externí odkaz: