Along with the geological characterisation and high-resolution global mapping of the surface of Mars with HRSC, in colour and 3D, the exploration of Phobos is another scientific priority for the Mars Express HRSC experiment. During the six years of the mission, the larger of the two moons has already been photographed 127 times by the HRSC camera system and its integrated Super Resolution Channel (SRC), which gives images with four times the magnification of the standard system. Mars Express has come as close as 93 kilometres to the 26.8 kilometres × 22.4 kilometres × 18.4 kilometres moon. Phobos circles the planet in an almost completely circular equatorial orbit at a distance of 6,000 kilometres.
The image shows the northern hemisphere of Phobos, pocked with innumerable meteor craters (N = North Pole). The exposure was made on 28 July 2008, during Orbit 5870, with the nadir channel of the HRSC, which is perpendicular to the surface. Mars Express was 351 kilometres away from Phobos at the time of the exposure and the resolution is 14 metres per pixel.
Credit: ESA/DLR/FU Berlin (G. Neukum).