Venus South Pole Double Vortex
These six different false-colour infrared images were taken by the Ultraviolet/Visible/Near-Infrared spectrometer (VIRTIS) between 12 and 19 April 2006, during the capture orbit around Venus.
The images taken at 5 μm were obtained at six different time slots and different distances from the planet (from left to right, top to bottom):
- 12 April: from 210 000 kilometres
- 13 April: from 280 000 kilometres
- 14 April, from 315 000 kilometres
- 16 April: from 315 000 kilometres
- 17 April: from 270 000 kilometres
- 19 April: from 190 000 kilometres
The planet's globe, imaged at different angles, was mapped onto an electronic mock-up of Venus, so to have the south pole always plotted at the centre of each single image.
Around the south pole it is possible to see a peculiar double-eye vortex structure, never clearly seen by any other Venusian mission before. The sequence of images shows the rotation and the shape variation of the double vortex over time. It is also possible to see the rotation of the terminator: the day side is visible in yellow and the night side is blue.
The images also show the presence of a collar of cold air around the vortex structure (dark blue), possibly due to the recycling of cold air downwards.