The massive double eye of the Venusian polar vortex has now merged into one enormous eye, as seen from the ESA's Venus Express spacecraft. That latest findings were released on Sept 23. Earlier observations during the 80's and 90's by various spacecraft in orbit about Venus, notably the Pioneer-Venus orbiter, had shown two vortices in the south polar region of the planet. But now it seems the two vortices have merged into one huge storm over 3000km wide.
Lamina flow in a cold environment...little or no friction between the cloud layers and with the high velocity of the zones, the formations hold their shape for a long time. It's probably a polar vortex which has formed and become a permanent feature, much like the GRS on Jupiter. The exact physics behind it is still problematical (although the EU crowd will have all the answers, no doubt).
Massive Venusian Polar Vortex
