Altimetry map of the surface Venus, April 1983.
© National Aeronautics & Space Administration / Science & Society
This map of Venus was created using information from the Pioneer Venus Orbiter. It was launched on 20th May 1978, and went into orbit around Venus in December 1978. It radar mapped 93% of the planet's surface as well as returning over 1000 images of the Venusian clouds. The map was made by the Masachusetts Institute of Technology. The red, yellow and green regions represent highland areas, while the blue areas are low-lying depresions in the planet's surface. The red region left of centre is the 11 kilometre high Maxwell Montes, the highest mountain on Venus. The impenetrable clouds of the Venusian atmosphere meant that nothing was known about the surface until the Soviet Venera probe landed and was briefly able to transmit images in 1975.