Sweeping over the South Pole (of Mars)
An unusual observation by Mars Express shows a sweeping view over the planets south polar ice cap and across its ancient, cratered highlands.
The image was taken by the high-resolution stereo camera on ESAs Mars Express on 25 February.
During normal scientific imaging, the camera typically takes images pointing straight down towards the surface, from around the closest point to the planet along the spacecrafts elliptical orbit at an altitude of about 300 km.
But in this unusual observation, known as a broom calibration image, Mars Express turned such that its camera panned over the surface far above the planet, close to its furthest point along its orbit, in this case at around 9900 km.
Importantly, as well as affording an unusual wide view, this allows the camera to record a range of features at the same illumination conditions, allowing essential calibration of the cameras sensors.
more
http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Sweeping_over_the_south_pole_of_Mars
link to high res images
http://www.esa.int/spaceinimages/Images/2015/09/Mars_south_pole_and_beyond