| Literature DB >> 18046395 |
G Piccioni1, P Drossart, A Sanchez-Lavega, R Hueso, F W Taylor, C F Wilson, D Grassi, L Zasova, M Moriconi, A Adriani, S Lebonnois, A Coradini, B Bézard, F Angrilli, G Arnold, K H Baines, G Bellucci, J Benkhoff, J P Bibring, A Blanco, M I Blecka, R W Carlson, A Di Lellis, T Encrenaz, S Erard, S Fonti, V Formisano, T Fouchet, R Garcia, R Haus, J Helbert, N I Ignatiev, P G J Irwin, Y Langevin, M A Lopez-Valverde, D Luz, L Marinangeli, V Orofino, A V Rodin, M C Roos-Serote, B Saggin, D M Stam, D Titov, G Visconti, M Zambelli, Eleonora Ammannito, Alessandra Barbis, Rainer Berlin, Carlo Bettanini, Angelo Boccaccini, Guillaume Bonnello, Marc Bouye, Fabrizio Capaccioni, Alejandro Cardesin Moinelo, Francesco Carraro, Giovanni Cherubini, Massimo Cosi, Michele Dami, Maurizio De Nino, Davide Del Vento, Marco Di Giampietro, Alessandro Donati, Olivier Dupuis, Sylvie Espinasse, Anna Fabbri, Agnes Fave, Iacopo Ficai Veltroni, Gianrico Filacchione, Katia Garceran, Yamina Ghomchi, Maurizio Giustini, Brigitte Gondet, Yann Hello, Florence Henry, Stefan Hofer, Gerard Huntzinger, Juergen Kachlicki, René Knoll, Kouach Driss, Alessandro Mazzoni, Riccardo Melchiorri, Giuseppe Mondello, Francesco Monti, Christian Neumann, Fabrizio Nuccilli, Jerome Parisot, Claudio Pasqui, Stefano Perferi, Gisbert Peter, Alain Piacentino, Carlo Pompei, Jean-Michel Reess, Jean-Pierre Rivet, Antonio Romano, Natalie Russ, Massimo Santoni, Adelmo Scarpelli, Alain Semery, Alain Soufflot, Douchane Stefanovitch, Enrico Suetta, Fabio Tarchi, Nazzareno Tonetti, Federico Tosi, Bernd Ulmer.
Abstract
Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole. The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition.Entities:
Year: 2007 PMID： 18046395 DOI： 10.1038/nature06209
Source DB: PubMed Journal: Nature ISSN： 0028-0836 Impact factor: 49.962