Venuss southern polar vortex reveals precessing circulation
Luz, D ; Berry, D L ; Piccioni, G ; et al. ; - ASI Sponsor
Apr - 2011
DOI: 10.1126/science.1201629
ISSN : 1095-9203 ;
journal : Science (New York, N.Y.)

Volume : 332 ; Issue : 6029
type: Article Journal

Initial images of Venuss south pole by the Venus Express mission have shown the presence of a bright, highly variable vortex, similar to that at the planets north pole. Using high-resolution infrared measurements of polar winds from the Venus Express Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument, we show the vortex to have a constantly varying internal structure, with a center of rotation displaced from the geographic south pole by 3 degrees of latitude and that drifts around the pole with a period of 5 to 10 Earth days. This is indicative of a nonsymmetric and varying precession of the polar atmospheric circulation with respect to the planetary axis.

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