The Venusian cloud system

These two images, respectively taken by the NASA/ESA Hubble Space Telescope in ultraviolet and by the NASA Galileo mission in infrared, show the complex cloud system on Venus. At the cloud top, the atmosphere rotates at a formidable velocity, with wind speeds of up to 360 kilometres per hour. Venus Express is designed to study the cloud system and what mechanisms cause this 'zonal super-rotation'.