The southern hemisphere of Venus in ultraviolet

This false colour picture of Venus was taken with the Venus Express Venus Monitoring Camera (VMC)and shows the southern hemisphere from the Equator (right) to the south pole; North is on the right of the picture.

The south pole is surrounded by a dark, oval bank of cloud in which there is a semi-circular, even darker band of cloud. A large number of differently shaped, sometimes striped or speckled bands of cloud can be seen from the pole towards the lower latitudes and the equator. Venus Express data gives rise to the conclusion that hotter air around the equator - that receives the most solar energy - rises in what are called convection cells from deep down in the atmosphere, moves towards the poles, cools down there, forms large swirls of cloud and then circulates almost parallel to the latitudes. In a super rotation, i.e. at much higher speeds than the planet itself, the bands of cloud rush round Venus. Venus Express has measured wind speeds of up to 360 kilometres an hour.

This picture was taken with the VMC ultra violet filter in wavelengths of 365 nanometres on 23rd July 2007 at a distance of 35 000 kilometres from Venus.

Credit: ESA/MPS/DLR/IDA.