Often spotted clouds blue sky of Earth, but Venus is never clear. This planet is permanently surrounded by a solid covering of carbon dioxide and sulfur dioxide, about 20 kilometers thick.
This image, taken by the European spacecraft Venus Express on December 8, 2011 when it was at about 30,000 miles from Earth, shows the top of the clouds of Venus in ultraviolet wavelengths.
The southern hemisphere of Venus occupies most of the image, with the South Pole at the bottom and near the top Ecuador. The clouds that cover the planet are about 70 miles above its surface.
The light and dark streaks that run through the cloud cover are caused by variations in the concentration of an unknown chemical absorbent. This image indicates that this substance Ecuador abounds about the planet, causing this region appear darker in ultraviolet wavelengths.
However, the clouds near the South Pole are much clearer. This could indicate a lower concentration of the absorbing substance, or the presence of a highly reflective aerosol in the upper layers of the atmosphere of Venus at these latitudes.
The shape of the clouds indicates that atmospheric dynamics is dominated by a strong circulation.
The whirlwinds of top indicate the presence of turbulent phenomena, contrasting with the smooth lines drawn by the laminar flow that dominates the middle and high latitudes.
By studying the evolution of certain traits and characteristics of clouds can be estimated wind speed, which in this case comes to exceed 100 meters per second. The atmosphere of Venus rotates at an amazing speed, completing a circle the planet every four Earth days, while the planet takes 244 to rotate on its own axis.