Topographical map of Acidalia Planitia
Topographical map of Acidalia Planitia
Using the HRSC stereo camera, digital terrain models can be derived that illustrate the topography of the region using false colours. The altitude allocation can be read from a colour scale at the upper left; north is to the right in the image. In the absence of 'sea level', the elevation data is referenced to an areoid – a modelled equipotential surface on which everything experiences the same gravitational attraction towards the centre of the planet.
The transition from the Martian highlands in the west – at the top in the image – to the lowlands of Acidalia Planitia is clear. The terrain falls by more than two kilometres over a distance of less than 100 kilometres. It is also easy to see that some of the large craters in the highlands are filled almost to the rim with material deposited there by flowing rivers a long time ago, whereas several younger, deep craters in Acidalia Planitia still retain their original bowl-shaped form and contain no sediment.
Copyright note:
As a joint undertaking by DLR, ESA and FU Berlin, the Mars Express HRSC images are published under a Creative Commons licence since December 2014: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO. This licence will also apply to all HRSC images released to date.