Mars is about to come into focus as never before, thanks to data from the European Space Agency's Mars Express High Resolution Stereo Camera.

Ordinary images can give spectacular bird's-eye views, but convey only part of the picture as they miss out on the topography, or vertical elevation, of the surroundings.

The new 3D Digital Terrain Models allow scientists to 'stand' on planetary surfaces.

The camera was designed to provide this information and the first comprehensive release of 3D data of a large part of the Martian surface is now ready.

"Understanding the topography of Mars is essential to understanding its geology," said Gerhard Neukum, a professor at the Freie Universität in Berlin, and principal investigator for the High Resolution Stereo Camera.

The Digital Terrain Models can instantly tell researchers the slope of hillsides or the height of cliffs, the altitude and slope of lava flows or desert plains.

"This data is essential for understanding how water or lava flowed across Mars," explained Professor Neukum.

It also helps planetary scientists to better interpret other data sets, for example the results of the Mars Advanced Radar for Subsurface and Ionosphere Sounding.

"Once we know where the surface is, we can correctly interpret the radar echoes we get from below it," said former ESA scientist Angelo Rossi, a member of the camera team.

The Mars Express Digital Terrain Models are the most detailed topographic data sets ever released for Mars, and were made possible by processing individual image swaths taken by the camera as Mars Express swept through its orbit.

The individual swaths are then put together into mosaics that cover large regions.