publication 18-February-2019 05:54:31

South-polar features on Venus similar to those near the north pole

Publication date: 29 November 2007

Authors: Piccioni, G. et al.

Journal: Nature
Volume: 450
Issue: 7170
Page: 637-640
Year: 2007

Copyright: Nature Publishing Group

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.

Link to Publication: http://www.nature.com/nature/journal/v450/n7170/full/nature06209.html


Last Update: 29 November 2007

For further information please contact: SciTech.editorial@esa.int