Mars Surface Now 90% Mapped in 3D
Mapping the surface of Mars in 3D is now 90% finished by the high-resolution stereo camera on the European Space Agency's Mars Express, about 9 years after the orbital insertion of the satellite.
The mosaic of the map consists of 2702 individual swaths of the martian surface, providing a record of all locations observed by the camera simultaneously in red, green, blue and nadir channels. Making those took the satellite 10 821 orbits, with 61.5% of the surface now mapped in high-resolution of 20 m per pixel or better. One of the more spectacular results came out this January with detailed and plastic topographical images of an ancient river valley (images of raw data and animation added below).
On top of the mapping, the orbiter which celebrates ten years since launch this June, is also performing mineralogical mapping of the surface, radar sounding of the subsurface structure down to the permafrost, precise determination of the atmospheric circulation and composition, and study of the interaction of the atmosphere with the interplanetary medium.
The map shown is formatted to be equatorially aligned, meaning that regions at the poles appear distorted - also, images that were particularly affected by dust or atmospheric effects have not been included in the mosaic. The subtle variation in colour tones are due partly to changes in dust content in the atmosphere, but mostly due to the change in solar elevation as the spacecraft moves around the planet, experiencing different illumination conditions.
Upon closer inspection, many well-known geological features are revealed. Towards the top left stands Olympus Mons, the tallest volcano in the Solar System at over 21 km high. A chain of three volcanoes making up the Tharsis Montes lies just below and to the right.
Moving further right again uncovers the Solar System's largest canyon, Valles Marineris. This giant cavern plunges 10 km deep and runs over 4000 km.
Assuming that good atmospheric conditions coincide with the appropriate orbits, Mars Express scientists hope that they might fill in the remaining gaps in the map in the coming years - although the current mission extension is running out in 2014.