The temperature maps of the venusian surface shown in this image were built thanks to direct measurements obtained by Venus Express' VIRTIS instruments (left), compared with surface-temperature predictions based on Magellan topographic data obtained in the early 1990s (right). VIRTIS, the Visible and Infrared Thermal Imaging Spectrometer aboard ESA's Venus Express, gathered the data combined into this mosaic on August 10, 2006, during a single orbit.