Mars topographical map. Three-dimensional composite satellite image of the surface of Mars. Topographical features are labelled in black. North is at top. Features visible include the Chryse Planitia (just left of centre), a plain with a diameter of around 840 kilometres, and Olympus Mons (far centre left), the tallest known volcano and mountain in our solar system. The map was created using data from the Mars Global Surveyor spacecraft's Mars Orbiter Laser Altimeter.